The Social Problem With Teenage Pregnancy - 1358 Words

The social problem with teenage pregnancy is one to be aware of. Throughout the years we have seen the numbers all across the spectrum. This being, the number of pregnant teenage girls has decreased in recent years, but on the other hand, has also been pretty high ten to twenty years ago. According to the CDC (Center for Disease Control), â€Å"In 2013, a total of 273,105 babies were born to women ages 15-19 years, for a live birth rate of 26.5 per 1,000 women in this age group. This is a record low for U.S. teens in this age group, and a drop of 10% from 2012† (CDC, 2015). When I saw this statistic I was shocked. It made me want to instantly know more about past years’ statistics as well as years to come and how these numbers will change in the coming future. If the rate of teen pregnancy dropped 10 percent in one year, will it continue to decrease? I am also curious to know why the numbers are dropping and if there is a specific reason for these numbers. So throughout this paper, I will explore the basics of teen pregnancy, including, why, and how it happens. Along side the basics, I will explore the specifics, including the rates for teen pregnancy, and if it is predicated these numbers will continue to decrease and the reason for the decrease in numbers. Then, the prevention and why it is important for teens to be informed of this social issue. As well as anything else I think I need to be fully informed on to help a client with a social issue like teen pregnancy.Show MoreRelatedThe Social Problem Of Teenage Pregnancy929 Words   |  4 Pagespositive. Occasionally, â€Å"average age† parents are not sufficiently prepared to deal with parenthood, thus a teenager is greatly less prepared. Therefore, teenage pregnancy has become a major social problem which fundaments should be understood in order to provide a solution to it. In order to understand a social problem such as teenage pregnancy, it is important to look firstly at its causes. In the first place, parents are of immense importance regarding a child’s development because they are theRead MoreTeenage Pregnancy And Parenthood As A Social Problem1466 Words   |  6 PagesTeenage pregnancy and parenthood as a social problem Question – To what extent should we regard the efforts of recent governments to reduce teenage pregnancy and early parenthood as successful? * Source 1 Williams-Wheeler, D. (2004). The unplanned pregnancy book for teens and college students, Virginia Beach, VA: Sparkledoll Productions. The information gathered from this source is definitely devoted to the topic of teenage pregnancy because it is a helpful guide to those handling unplanned pregnanciesRead MoreThe Socio Economic Factors Of Teenage Pregnancy1517 Words   |  7 PagesTeenage pregnancy is normally identified as deprived life choice, for example, tasks of teenage parenting have long-term impact on the mental health of the mother and children (Statistics New Zealand, 2003). It is important to identify the socio economic factors of teenage pregnancy to lower the chances of mental health problems in young mothers. In this paper the aim is to analyse the main socio economic factors of teenage pregnancy and discuss how it affects the mental health of an adolescent motherRead MoreEffects Of Teen Pregnancy On Teenage Pregnancy1620 Words   |  7 PagesServices). Teenage females associated with childbearing expose themselves to many risks and negative effects that can affect their future. Females result with m any consequences due to teenage pregnancy. This paper will strictly focus on the effects females experience through teenage pregnancy. The reader will be able to develop an overall understanding of the causes of teen pregnancy. Also, the reader will be able to distinguish the psychosocial effects on the girl during adolescent pregnancy. The readerRead MoreThe Factors Of Teenage Pregnancy1558 Words   |  7 PagesTeenage pregnancy is normally identified as a deprived life choice, for example, tasks of teenage parenting have long-term impact on the mental health of the mother and children (Statistics New Zealand, 2003). It is important to identify the socioeconomic factors of teenage pregnancy to lower the chances of mental health problems in young mothers. In this paper the aim is to analyse the main socioeconomic factors of teenage pregnancy and discuss how it affects the mental health of an adolescent motherRead MoreTeenage Pregnancy And Teen Pregnancy1546 Words   |  7 PagesT eenage pregnancy is pregnancy in human females under the age of 20 at the time that the pregnancy ends. Low-income communities have the highest teenage pregnancy rates in the United States. Because of the fact that this is a very controversial issue in the United States, it is very important that most questions be addressed. Questions like, why is a teenage girl in Mississippi four times as likely to give birth as a teenage girl in New Hampshire? Or why is the teen birth rate in Massachusetts 19Read MoreMotherhood and Pregnancy1429 Words   |  6 Pagesmother victorious in her life. In this modern world women’s attitude against pregnancy and being a mother is changing accordingly. There occurs so many miscarriages and maternal death during the pregnancy. A woman should be physically, and more over mentally set to have a baby in her womb. Considering the biological fitness of health it’s said that safer age to be get pregnant is in between 20 to 29. Early pregnancy in the teenage age of 13 to 20 and the delayed motherhood age after 35 is challenging toRead MoreTeenage Pregnancy Essay674 Words   |  3 PagesTeenage Pregnancy Over one million teenage girls become pregnant each year. In the next 24 hours, about 3,312 girls will become pregnant. In addition, 43% of all adolescents become pregnant before the age of 20. These are incredible statistics when you consider that there are only 31 million females. The United States has the highest adolescent pregnancy rate in the developed world. As statistics show one in nine women between the ages of 15 through 19 become pregnant each year. Also, everyRead MoreTeenage Moms That Are Still In High School Get Pregnant1391 Words   |  6 PagesTeenage moms that are still in high school get pregnant at a young age, and are not able to support themselves or their child. There were just under a quarter million pregnancies in women ages fifteen to nineteen in 2014. About eighty-five percent of these pregnancies are unplanned, which in any population can increase the risk for problems. The biggest risk for teen mothers is delaying prenatal care or worse, about seven perc ent received no care at all. According to CDC, In 2014, almost 250,000Read MoreTeenage Pregnancy Essay1400 Words   |  6 Pageseconomic growth. Evidently, the younger generation represents the larger population of Belize and as suggested by a report, commissioned by the United Nations, Belize encompasses the highest rate of teenage pregnancy in the Caribbean followed by Guyana and Jamaica. Based on the media perspective, teenage pregnancy is a rising issue in Belize that should be taken more seriously. It’s an epidemic ruining lives and perpetuating poverty. According to Sheila Roseau, Director of UNFPA SROC, the birth-rates in

Into The Wild By Jon Krakauer Essay - 1855 Words

Into the Wild by Jon Krakauer, published in 1996, discusses the life and death of young adult and adventurer, Christopher McCandless. Krakauer, a journalistic writer from the Pacific Northwest, was quite fond of adventure as well, having a passion for climbing. His infatuation for risk and adventure gave him great interest in McCandless’s story of leaving the comfort of his home in Virginia and wandering across the country, ultimately landing himself to the brush of Alaska, where his journies came to a close and he died. Into the Wild goes through events from 1990 to 1992, going through McCandless’s trips and the people he met, to his family life and investigations of his death, to other adventurers that can he can be compared to. Krakauer outlines the story through use of different sources including McCandless’s family and the people he met, along with his own story and that of other similar people such as Everett Ruess. The controversy over McCandless†™s life choices and the story of his life bring about numerous concepts that are universal to human experience. Into the Wild makes important remarks about courage, isolation, and passion, which can be looked into further when compared to the works â€Å"In Praise of Failure†, â€Å"Embracing a Life of Solitude†, and â€Å"The Wild Truth†, respectively. Chris McCandless’s experiences and journey into the Alaskan brush shows prime examples of courage and strength. Throughout day to day life, bravery is required to get through tougherShow MoreRelatedInto the Wild by Jon Krakauer563 Words   |  2 PagesJon Krakauer presents Into The Wild a tragic tale of a young ambitious man who is motivated to go into the wilderness and discover his true identity.Jon krakauer conveys many messages to his readers through Chris McCandless, and his messages often offer a warning to society.we will furture idenitfy how the author delievers the warning to society and what effect it can have upon society today.Three of the very important messages he empatizes on are the societies influence on people,the essence ofRead MoreThe Wild By Jon Krakauer1096 Words   |  5 PagesAllyssa Mikes July 2012 Into the Wild Mr. Fertmann Throughout the non-fictional novel Into the Wild, the author Jon Krakauer catches the reader’s interest early on in the book. Krakauer takes us on a journey, telling the story of young Chris McCandless’ adventures after abandoning everything he owned. Krakauer fully emerged himself into the study of McCandless’ life’s adventures and soon developed a deep understanding of who he was and how he impacted to world. Krakauer connected with McCandless in anRead MoreInto The Wild By Jon Krakauer946 Words   |  4 Pagescompelling novel â€Å"Into The Wild† by Jon Krakauer the character and intelligence of the youth in men is questioned. Through the pieced together 200 page novel we are introduced to Christopher Johnson McCandless also known as â€Å"Alex Supertramp†. A ripe 24 years of age he chose to question our reality and his meaning of life that is given to us by hitchhiking across America to the Alaskan wilderness, where after four months in the last frontier he is found dead. Krakauer throughout the novel shows thatRead MoreInto The Wild By Jon Krakauer1330 Words   |  6 Pagesshared.† - Jon Krakauer Into the wild. Jon Krakauer, the author of Into the Wild told the story of Chris McCandless. Chris escaped reality and went to go live off the land in Alaska, hoping to live a simpler life. In the novel, Into the Wild by Jon Krakauer, Chris McCandless shared a similar philosophy with Jack London, as they both have a strong passion for Alaska, they both appreciated they beauty of nature, and both wanted to be reborn. In the novel, Into the Wild by Jon Krakauer, Chris McCandlessRead MoreInto The Wild By Jon Krakauer1349 Words   |  6 PagesSummary Into the Wild by Jon Krakauer is a true story about Chris McCandless who is found dead in the Alaskan wild during September 1992. After discovering that his father had a secret secondary family when Chris was young, Chris pushes away his friends and family and eventually isolates himself. He obtains $25,000 from his parents by lying about attending law school and drives away from home, deserting his real name. He later leaves his car in Georgia after an engine breakdown due to rain damageRead MoreInto The Wild By Jon Krakauer1013 Words   |  5 Pages Into the Wild, by Jon Krakauer, narrates the life of adventurer and free spirit Christopher McCandless, who died August 1992 in the Alaskan wilderness; however, his journey still remains relevant in today’s pop culture due to the unresolved controversy of whether he is a saintly role model or hubristic fool. Krakauer openly states that he â€Å"won’t claim to be an impartial biographer† (Author’s Note) due to the parallels he struck with McCandless, and provides a more idealistic approach to the biographyRead MoreInto the Wild by Jon Krakauer1516 Words   |  7 PagesRosselini, John Waterman and Carl McCunn. They all went to Alaska, just like Chris and died. After that Chris continued to canoe and got caught by the US officers when he was trying to get back into the US from Mexico. So he spent a night in jail. Krakauer then compared Chris to Everett Reuss. They both changed their names and they both disappeared. Chris applied for an ID as Alex Supertramp and found a job in Los Angeles. New York Times published about Alex’s death. Jim Gallien and Wayne WesterbergRead MoreThe Wild By Jon Krakauer1522 Words   |  7 Pagesvictories.† (Richard M. Nixon). In his investigative biography, Into the Wild, Jon Krakauer, expresses that even though young people can be ignorant and take treacherous risks, these can be used as knowledge enhancers and can be life changers. Krakauer gives us insight by giving examples of what risk really are, how people take them, and how it actually affects those people. Throughout the whole book there are instances where krakauer uses real life examples of things that have happened where people haveRead MoreInto The Wild By Jon Krakauer Essay1237 Words   |  5 Pages Jon Krakauer s novel â€Å"Into the wild†, Is a story about a young man named Christopher McCandless or â€Å"Alex Supertramp† who went on a self discovering odyssey in which he had traveled around the U.S. The story surrounds Chris and his travels and what he had done at the time, leading to his death in August 1992. Thus the story takes a direction in the viewpoints of the people Alex has come across through in his travels. It speaks about what he had done at the time of his journey before he hadRead MoreInto the Wild: by Jon Krakauer1186 Words   |  5 Pagessense Krakauers natural liking for McCandless. He was sympathetic to McC andless, based on Krakauers sense of a shared experience in their youth and up until McCandless eventual death and Krakauers perceived near death experience on the Devils Thumb. I believe the author’s main point and perspective was formed from his own experience and relationship with his father. While the situations were basically reversed with Chris not approving of his father and Lewis Krakauer disappointed in Jon for not

The Science Shtuff free essay sample

They must examine three plentiful similar species to determine which one is most similar to curus . It is hoped that this plant will also produce curol, the cancer curing drug. classified chemical. is on the Botana Lab Procedure: The students first compared the structural characteristics of the plants to try to determine which species was the closest structurally to Botana curus . †¢ Students examined the structural (physical) characteristics of the leaves of these plants to determine which one is structurally closest to Botana curus . Leaves are actual size. ) Physical factors deal with the form or structure of the leaf. The physical factors of a leaf include its size shape, color, and venation (How are the veins organized? ). Fill in the following table: Leaf Species BC Color Light Green Size Shape Venation Veins connected to center vein branch off to sub-veins All veins are directly connected to center vein All veins are directly connected to center vein Veins connected to center vein branch off to sub-veins Species X Dark Green Species Y Medium Green Species Z Light Green Base on the physical characteristics of the leaf, which species appears to be most similar to Botana curus? Explain your answer.  © 2006 Gregory Arnold Study Guide The New Labs Page: 2 †¢ Students examined the structural (physical) characteristics of the seeds of these plants to determine which one is structurally closest to Botana curus. (As viewed under a dissecting microscope at 10X. ) Physical factors of a seed include its size shape, color, and distinguishing marks such as the scaring where it was attached to the plant. Fill in the following table: Seed Species BC Color Beige Size Shape Distinguishing Marks Species X Green Species Y White Species Z Black Base on the physical characteristics of the seed, which species appears to be most similar to Botana curus? Explain your answer. †¢ Students used a microscope to examined the internal structural characteristics of the stems of these plants to determine which one is structurally closest to Botana curus. (Viewed under a microscope at 50X power. ) Physical factors of a stem include the size, shape and placement of its vascular bundles. Because these prepared slides of stems were stained to make the vascular bundles more clear, their color is not significant. (Note: Some of the bundle cell walls are so thin, that they are hard to distinguish from the other cells of the stem. )  © 2006 Gregory Arnold Study Guide The New Labs Page: 3 Fill in the following table: Stem Species BC Vascular Bundle Size Shape Vascular Bundle Placement Species X Species Y Species Z Base on the physical characteristics of the stem, which species appears to be most similar to Botana curus? Explain your answer. †¢ Based on all of the observed physical (structural) characteristics, hypothesize which plant was most similar to Botana curus. Why? After comparing the physical characteristics of the plants, the students compared the chemical (molecular) characteristics to try to determine which species was the closest molecularly to Botana curus. †¢ Students used paper chromatography to separate the plant pigments to determine which plant has the most similar plant pigments of Botana curus. Base on the chromatography results, which species appears to be most similar to Botana curus? Explain your answer. 2006 Gregory Arnold Study Guide The New Labs Page: 4 †¢ Students used an indicator to determine the presence of enzyme M, an enzyme that is usually present when the cancer drug is present. A fizzing action indicates the presence of enzyme M. (An indicator is a chemical that produces an observable change if the substance being tested for is present. ) Base on the indicator results for the presence of enzyme M, which species appears to be most similar to Botana curus? Explain your answer. †¢ Students simulated gel electrophoresis to determine which plants DNA is most similar to the DNA of Botana curus. How a gel electrophoresis works: 1. Scientists use a special enzyme that cuts the DNA at specific base sequences. In the above example, the special enzyme cut the DNA in the middle of every C-C-G-G base sequence. 2. The DNA fragments are put into the wells located on top of the device, and then the electricity is turned on. 3. The negative charged DNA fragments move towards the positive plate. The smaller the fragment, the faster it moves through the gel. (The three base fragment of Species Y moved the most while the 22 base DNA fragment of species X moved the least. Base on the results of the gel electrophoresis, which species appears to be most similar to Botana curus? Explain your answer.  © 2006 Gregory Arnold Study Guide The New Labs Page: 5 †¢ Using the DNA sequence, determine the base sequence of its complementary messenger RNA molecule. Then use the universal genetic code to translate the messenger RNA base sequence into the amino acid sequence of the protein being p roduced. How to determine the amino acid sequence from a strand of DNA? 1. Separate the DNA molecule into groups of three bases. 2. Produce your RNA codons by writing the complementary messenger RNA (mRNA) bases. C —gt; G, G —gt; C, T —gt; A, and A —gt; U (There are no Ts in RNA) 3. Use the mRNA codon to determine the amino acid. (Note: Two different codons can code for the same amino acid. It is therefore possible for two different DNA molecules producing identical proteins. ) (Note: The amino acid molecules are represented by the three letters after the parenthesis (}).  © 2006 Gregory Arnold Study Guide The New Labs Page: 6 Fill in the following table: How is The DNA and protein molecule of the three species being tested different than Botana curus? S pecies Species BC DNA Sequence Protein Sequence Species X Species Y Species Z †¢ Based on all the observed structural and molecular characteristics, hypothesize which plant is most similar to Botana curus. Why? This is a very important essay involving Biodiversity. It comes directly from the New York State required lab #1. Read it carefully! The Biodiversity Crisis Plant and animal species are being lost at a rate that is unprecedented in the history of life. Human activities are responsible for much of this biodiversity crisis. Some biologists estimate that within the next century, half of Earth’s current species may become extinct. Extinction and the loss of biodiversity occurs when species do not have adaptations that enable them to survive environmental changes. Human activities such as destruction of natural habitats and pollution are thought to be the major environmental factors causing the decline of species, but others are also important. Overhunting, introduction of foreign species that compete with native species, and removal of predators have also played a significant role in endangering some species. Why should we worry about the loss of biodiversity? We depend on many species for food, clothing, shelter, oxygen, soil fertility—the list goes on and on. Large-scale extinctions of other species may be a warning to us that we are altering the biosphere so rapidly that our species is threatened too. Biodiversity ensures the availability of a rich variety of genetic material that may lead to future agricultural or medical discoveries having significant value to humankind. Some species have been used as sources for medicines  © 2006 Gregory Arnold Study Guide The New Labs Page: 7 and other useful products. Scientists now use genetic engineering to transfer desirable genes from one species to another. As diversity is lost, potential sources of these genetic materials may be lost with it. Biodiversity also increases the stability of the ecosystem. Every population is linked, directly or indirectly, with many others in an ecosystem. Disruptions in the numbers and types of one species can upset ecosystem stability. This means that extinction of one species can accelerate the rate of extinction for other species. Endangered species hold medicinal, agricultural, ecological, commercial, and aesthetic value. They must be protected so that future generations can experience their presence and value. All students should have learned: 1. An indicator is a chemical that is used to indicate the present of substance being tested. will occur if the test substance is present. Some indicators are: Indicator Iodine (amber) Benedicts Solution (Blue) pH indicator (Bromthymol Blue) Test substance starch Simple sugar If solution is an acid, neutral or base An observable change Observable change Turns blue-black to black Turns from blue to orange-red Acid yellow Neutral green Base blue 2. Physical characteristics involve the structure or appearance of the organism. They are not as reliable for determining close relationships as comparing DNA or protein. Many unrelated organisms may have some similar structures but will also have many structures that are different. Depending on what structures you are studying, you might establish an evolutionary relationship that does not exist. For example, If the physical characteristic under study was the presence of hair, you might say that a Mexican hairless dog is closer to a Timber Rattlesnake than to a German Shepherd dog. However, if you compared their DNA or proteins, you would find a very close evolutionary relationship exists between a Mexican Hairless dog and the German Shepherd dog. Organism German Shepherd dog Mexican hairless dog Timber Rattlesnake Presence of Hair Yes No No 3. Chromatography can separate different substances because their molecules flow through a medium, usually paper, at different rates. They flow at different rates because some molecules stick (adhere) to the paper more than other molecules. The rate of flow depends on the solvent used and the type of paper. The molecules can be identified by comparing the test samples with known substances. Chromatography is often used to separate pigments which are often made up of protein. Similar pigments might indicate an evolutionary relationship. DNA is found in the nucleus of the cell. It contains a code that controls the production of protein by organelles known as ribosomes, which are located outside the nucleus. It is able to do this because the DNA code can be transferred to messenger RNA (mRNA) which can leave he nucleus and travel to the ribosomes. Once at the ribosome, each RNA codon (three bases) will code for a particular amino acid molecule. (See the Universal Genetic Code Chart on page 6 of this booklet. ) For example: DNA molecule: ATGGCACCC RNA molecule: UACCGUGGG Protein Molecule: TYR ARG GLY Gel electrophoresis is a technique that can be used to determine how similar two or more strands of DNA are to one another. Gel electrophoresis involve the following steps: †¢ Obtain a sample of DNA from cells of any type of tissue or from most secretions of the organism. You dont need a lot of DNA because it can be easily duplicated. †¢ Use special enzymes to break down the long DNA molecules into smaller fragments. 4. 5.  © 2006 Gregory Arnold Study Guide The New Labs Page: 8 †¢ †¢ †¢ †¢ Place the DNA fragments of each organism into its own well and turn on the electricity. The electricity causes all of the fragments to move towards the positive side of the apparatus. Banding is produced because the smaller the fragment the faster it moves. The more similar the banding produced between species, the more similar the DNA and the closer the species are related 6. Once you have used some or all of the above methods you can draw a diagram representing the evolutionary relationships between organisms. Example 1: Example 2:  © 2006 Gregory Arnold Study Guide The New Labs Page: 9 Name: Topic 10A Base your answers to questions 1 through 3 on the information below and on your knowledge of biology. Scientists found members of a plant species they did not recognize. They wanted to determine if the unknown species was related to one or more of four known species, A, B, C, and D. The relationship between species can be determined most accurately by comparing the results of gel electrophoresis of the DNA from different species. The chart below represents the results of gel electrophoresis of the DNA from the unknown plant species and the four known species. . Scientists hypothesize that cabbage, broccoli, cauliflower, and radishes developed along a common evolutionary pathway. Which observation would best support this hypothesis? (1) Fossils of these plants were found in the same rock layer. (2) Chloroplasts of these plants produce a gas. (3) These plants live in the same environment. (4) These plants have similar proteins. Base your answers to questions 5 through 7 on the information below and on your knowledge of biology. Paper chromatography can be used to investigate evolutionary relationships. Leaves from a plant were ground and mixed with a solvent. The mixture of ground leaves and solvent was then filtered. Using a toothpick, twenty drops of the filtrate (material that passed through the filter) were placed at one spot on a strip of chromatography paper. This procedure was repeated using leaves from three other species of plants. A separate strip of chromatography paper was prepared for each plant species. Each of the four strips of chromatography paper was placed in a different beaker containing the same solvent for the same amount of time. One of the laboratory setups is shown below. . The unknown species is most closely related to which of the four known species? Support your answer. [1] 5. State one reason for using a new toothpick for the filtrate from each plant. [1] 2. Identify one physical characteristic of plants that can be readily observed and compared to help determine the relationship between two different species of plants. [1] Ans: 3. Explain why comparing the DNA of the unknown and known plant species is probably a more accurate method of determining relationships than comparing only the physical characteristic you identified in question 2. [1] 6. State one way the four strips would most likely be different from each other after being removed from the beakers. [1] 7. State how a comparison of these resulting strips could indicate evolutionary relationships. [1]  © 2006 Gregory Arnold Study Guide The New Labs Page: 10 Base your answer to question 8 on the portion of the mRNA codon chart and information below. 12. An indicator for a protein is added to a solution that contains protein and to a solution that does not contain protein. State one way, other than the presence or absence of protein, that the two solutions may differ after the indicator has been added to both. 1] Series I represents three mRNA codons. Series II includes a mutation of series I. Series I AGAUCGAGU Series II ACAUCGAGU 8. How would the amino acid sequence produced by the mutant strand (series II) compare to the amino acid sequence produced by series I? (1) The amino acid sequence would be shorter. (2) One amino acid in the sequence would change. (3) Th e amino acid sequence would remain unchanged. (4) More than one amino acid in the sequence would change. Base your answers to questions 9 through 11 on the diagram below and on your knowledge of biology. Letters A through L represent different species of organisms. The arrows represent long periods of geologic time. Base your answers to questions 13 through 17 on the information and diagram below and on your knowledge of biology. The four wells represented in the diagram were each injected with fragments that were prepared from DNA samples using identical techniques. 13. This (1) (2) (3) (4) laboratory procedure is known as cloning gel electrophoresis chromatography use of a dichotomous key 14. The arrow represents the direction of the movement of the DNA fragments. What is responsible for the movement of the DNA in this process? [1] 9. Which two species are the most closely related? (1) J and L (3) F and H (2) G and L (4) F and G 15. The four samples of DNA were taken from four different individuals. Explain how this is evident from the results shown in the diagram. [1] 10. Which species was best adapted to changes that occurred in its environment over the longest period of time? (1) A (3) C (2) B (4) J 11. Which two species would most likely show the greatest similarity of DNA and proteins? (1) B and J (3) J and K (2) G and l (4) F and L 16. Identify the substance that was used to treat the DNA to produce the fragments that were put into the wells. [1]  © 2006 Gregory Arnold Study Guide The New Labs Page: 11 Base your answers to questions 17 through 19 on the information provided and on your knowledge of biology. A student observed the physical characteristics of seven organisms and prepared the data table below. Base your answers to questions 20 through 22 on the information below and on your knowledge of biology. Based on their analysis of the differences in amino acid sequences of one kind of protein, scientists prepared the evolutionary tree shown below. One of the students classmates sorted the seven organisms into two groups as shown below. 20. According to this diagram, the DNA of which pair of organisms would show the greatest similarity? (1) penguin and turtle (3) snake and tuna (2) horse and donkey (4) turtle and rabbit 21. Older systems of classification always placed penguins, chickens, ducks, and pigeons in the bird group and turtles and snakes in the reptile group. Does this diagram support the older system of classification? Explain your answer. [1] 17. Which characteristic from the data table did the student use to group the organisms? [1] 8. Another classmate suggested that the earthworm is more closely related to the jellyfish than to any other organism observed. State the evidence from the data table that the student most likely used for this suggested relationship. [1] 22. According to this diagram, is the pig more closely related to the dog or the kangaroo? Justify your answer. [1] 19. Fish and snakes are very differ ent organisms, yet they have many similarities. Provide a biological explanation for the fact that fish and snakes have so many characteristics in common. [1]  © 2006 Gregory Arnold Study Guide The New Labs Page: 12 Base your answers to questions 23 through 26 on the information and diagram below and on your knowledge of biology. The diagram below shows the results of a test that was done using DNA samples from three bears of different species. Each DNA sample was cut into fragments using a specific enzyme and placed in the wells as indicated below. The DNA fragments were then separated using gel electrophoresis. 27. R , S , and T are three species of birds. Species S and T show similar coloration. The enzymes found in species R and T show similarities. Species R and T also exhibit many of the same behavioral patterns. Show the relationship between species R , S , and T by placing the letter representing each species at the top of the appropriate branch on the diagram below. [1] 23. Which two bears are most closely related? Support your answer with data from the test results. [2] 24. Identify one additional way to determine the evolutionary relationship of these bears. [1] 25. Gel electrophoresis is used to separate DNA fragments on the basis of their (1) size (3) functions (2) color (4) chromosomes 26. Identify one procedure, other than electrophoresis, that is used in the laboratory to separate the different types of molecules in a liquid mixture. 1]  © 2006 Gregory Arnold Study Guide The New Labs Page: 13 Lab Activity 2 Making connections In this lab, students are introduced to scientific experimentation by asking them to make connections between patterns that can be observed in the natural world. For instance, when one exercises, the heart rate increases. Is there a connection? — Sc ientific experimentation can be conducted to see if there is actually a connection. Lab Procedure: Students are asked to determine their average resting heart rate by taking their pulses over the course of three trials. For each trial, students counted the number of pulses they felt in their wrists or necks for twenty (20) seconds. This number was multiplied by three (3) to get a good estimate the number of pulses in a minute. Students organized the data by completing a class data table. Each student put their data in a table that was on the board. It should have looked like the table below. Class Results: Average Pulse Rates Tables are used to organize data! We can already see a pattern all of the student heart rates are between 51 and 80! A graph can be drawn to make this pattern even more graphic. Add your average heart rate to this graph Some students were asked to exercise. When they did, their pulse (heart rate) increased.  © 2006 Gregory Arnold Study Guide The New Labs Page: 14 In the second part of Lab Activity #2, the students explored how fatigue affect muscle performance by squeezing a clothespin using only two fingers. Students counted the number of times they could squeeze a clothespin in a minute. Recorded the data and then immediately counted the number of times they could squeeze a clothespin a second minute. Most students could not squeeze the clothespin as many times the second trial as they could the first trial. Will your muscles become fatigue by squeezing a clothespin? Do the following activity to find out! Squeeze a clothespin using the two fingers pictured as many times as you can in 1 minute. Record the number in the space provided below and then immediately see how many times you can squeeze the clothespin a second minute. Record that number in the space provided below. Number of squeezes per minute: 1st minute: 2nd minute: In the last part of Lab Activity #2, the students did an original experiment to determine if exercise could increase ones clothespin squeezing rate. Using family members and friends as subjects, students collected the following data: age. height. weight. sex. relationship. number of times able to squeeze clothespin without exercising. number of times able to squeeze clothespin after running in place for 2 minutes. Every experiment had to have at least 10 subjects. The control data included the number of times the subject could squeeze the clothespin in one minute without exercising, while the experimental data included the number of times the subject could squeeze the clothespin in one minute after exercising. Students constructed a data table for organizing the data. To determine the effect of the exercise, the student compared the data in the control group to the data in the experimental group. There was no consistent conclusion. Some students concluded that exercising before clothespin squeezing increased the number of times the clothespin could be squeezed while other students concluded the opposite. It was obvious that a larger, more controlled study was necessary to determine if exercise enhanced the performance of clothespin squeezing. All students should have learned: 1. When a person exercises, certain cells such as muscle cells use more energy than when the person is resting. These cells obtain energy by the process of cellular respiration. Cellular respiration occurs in the cells mitochondria. The energy released by breaking the bonds of glucose (sugar), with the aid of oxygen, is used to make ATP. Carbon dioxide is given off by the cell as a waste product. 2. Homeostasis is the process where the body maintains its chemistry and vital measurements within normal limits. When a person begins to exercise, cells use more energy and therefore begin to remove more oxygen and glucose from the blood while releasing more carbon dioxide to the blood. Internal receptors in the body sense these changes and react by: a. Increasing the heart rate in order to increase the flow of the circulating blood that is carrying the oxygen and glucose to the muscle cells and the carbon dioxide from the muscle cells. b. Increase the respiratory rate to quicken the exchange of oxygen and carbon dioxide between the air in the lungs and the blood in the circulatory system. . Increase the release of glucose by the liver, as directed by hormones from the pancreas. d. If the body becomes warm, blood, carrying heat, will be directed towards the skin and the body will begin to sweat. As the sweat evaporates, heat is carried away from the skin, cooling the body (feedback mechanism).  © 2006 Gregory Arnold Study Guide The New Labs Page: 15 3. A summary of the body reaction to exer cise is in the chart below. Systems Circulatory Responses 1. Heart rate (pulse) increases 2. Blood flows quicker Implications 1. An increase flow of oxygen and glucose flow to the muscle cells while carbon dioxide is moved away quicker. 2. An increase flow of carbon dioxide to the lungs and oxygen away from the lungs. 1. An increase supply of air in the lungs. Oxygen diffuses from the air into the blood while carbon dioxide diffused from the blood into the air in the lungs. 1. Glucose (sugar) is released into the blood by the liver. 1. The heart beats faster. 2. Blood vessels dilate (open) allowing greater blood flow. 3. If the body is warm, sweat begins to flow. Respiratory 1. Breathing rate increases 2. Breathing depth increases 1. Pancreas releases a hormone 1. Increase impulses from brain Endocrine Nervous 4. Muscle fatigue is mainly caused by two factors, a lack of oxygen and/or glucose, and/or the build up of wastes. When muscle cells do not get enough oxygen, a substance called lactic acid is produced. If a sufficient quantity of lactic acid is present, the muscle will begin to stiffen or cramp. This actually helps the person by preventing damage to the muscle due to over exercising. An hypothesis is a proposed outcome of an experiment. It has to be proved correct by analyzing the data from an experiment. Hypotheses are often written in terms of a cause and effect. If something happens, then something else happens. An example of an hypothesis is: If students study more, then test grades will increase. The cause is more studying and the effect is higher test grades. Can you write an hypothesis concerning the number of deer in an area? 5. 6. Every experiment must have a control group and an experimental group. Both groups should be the same except that the experimental group will be given the treatment that is being tested. Good experiments will be testing only one variable, called the independent variable. In one experiment you can test the effect of sunlight on the growth of corn plants and in another experiment you can test the effects of sunlight on the growth of corn. However, you cannot test both the effects of water and sunlight on the growth of corn in the same experiment. (Experiments can have more than one dependent variables. The dependent variable is what changes as result of changing the independent variable. For the experiment testing the effects of sunlight on the growth of corn, you could measure the weight of the leaves, stalk, fruit, and roots. That 4 dependent variables for the one independent variable. ) When a scientist performs an experiment, he/she must collect data. Most scientists will collect numbers or measurements. In order to indicate growth, a scientist might measure the height, length or weight of the organism. Sometimes, as with bacteria, growth can be determined by simply counting the number of colonies. Scientist will first write the experiment results into data tables. Once complete, the data tables can be organized into graphs. Graphs will often highlight the relationship between the cause and effect of the hypothesis. In order for an experiment to be reliable, it must have a significant number of subjects being studied. †¢ One (1) is totally unreliable. It is called a testimonial. If anyone ever tries to sell you a product based on testimonials, avoid the product. There are always exceptions, and advertisers will use these exceptions to sell their product. †¢ Ten (10) is a small number and would be unreliable because one or two exceptions would greatly change the data and the results of the experiment. †¢ Fifty (50) is an okay number. Fairly good data can be produced at low cost. Exceptions would not have that much effect on the results of the experiment. †¢ One hundred (100) is a good number of subjects. It will produces reliable data but at greater cost. †¢ Five hundred or more (gt;500) is aa excellent number of subjects. It will produces very reliable data but at a great cost. 7. 8. 9. 1 0 . To see if the treatment is effective, the experimental group results must be compared to control group results.  © 2006 Gregory Arnold Study Guide The New Labs Page: 16 Name: Topic 10B Base your answers to questions 1 through 4 on the data table below and on your knowledge of biology. A group of students obtained the following data: 7. A student squeezed a clothespin as many times as possible in a 30-second time period. The student repeated this procedure nine more times in quick succession. The data obtained are in the chart below. 1. The activity of which body system was measured to obtain these data? [1] Ans: 2. The activity of which other body system would be altered as a direct result of the exercise? [1] Ans: 3. What effect would exercise have on the system you identified in question 68? 1] Base your answers to questions 8 and 9 on the information below and on your knowledge of biology. In an investigation, 28 students in a class determined their pulse rates after performing each of three different activities. Each activity was performed three times during equal time intervals. The average results are shown in the graph below. State one hypothesis that this data would support concerning the relationship between number of trials and number of squeezes in 30 s econds. [1] 4. Explain how this change in pulse rate helps maintain homeostasis in muscle cells. 1] 5. A student hypothesizes that the pulse rate of a person and background music that is playing are related. The student designs an experiment to test this hypothesis. What would be an appropriate control for this experiment? [1] 8. Before constructing the graph it would have been most helpful to organize the results of the investigation in (1) a research plan (3) a data table (2) an equation (4) a generalization 9. Some students concluded that males always have a higher pulse rate than females. Does the graph support this conclusion? Justify your answer. [1] An increase in heart rate will most likely result in (1) a decrease in metabolic rate (2) an increase in pulse rate (3) an increase in cell division (4) a decrease in body temperature  © 2006 Gregory Arnold Study Guide The New Labs Page: 17 10. A student measures his pulse rate while he is watching television and records it. N ext, he walks to a friends house nearby and when he arrives, measures and records his pulse rate again. He and his friend then decide to run to the mall a few blocks away. On arriving at the mall, the student measures and records his pulse rate once again. Finally, after sitting and talking for a half hour, the student measures and records his pulse rate for the last time. Which graph below best illustrates the expected changes in his pulse rate according to the activities described to the right? 12. On a television talk show, a guest claims that people who exercise vigorously for 15 minutes or more every day are able to solve math problems more rapidly than people who have no vigorous exercise in their daily routine. Describe a controlled experiment that could be conducted to test this claim. In your description be sure to: †¢ state the purpose of the experiment [1] †¢ state why the sample to be used should be large [1] †¢ describe how the experimental group will be treated and how the control group will be treated [2] †¢ state the specific data to be collected during the experiment [1] †¢ state one way to determine if the results support the claim [1] 11. An experiment was designed to see what effects ibuprofen would have on laboratory mice. Large numbers of male mice and an equal number of female mice were used in this investigation. The male mice were placed in an area with food and water. The female mice were placed in a separate area of the same size. The female mice were given additional food and water. The males were each given 100 milligrams of ibuprofen each day, mixed with their food, and the females were each given 50 milligrams of ibuprofen each day, mixed with their food. Identify two errors in the design of this investigation. [2] (1) (2)  © 2006 Gregory Arnold Study Guide The New Labs Page: 18 13. When a person exercises, changes occur in muscle cells as they release more energy. Explain how increased blood flow helps these muscle cells release more energy. 1] Base your answers to questions 14 through 16 on the information and diagram below. An investigation was carried out using the two setups shown below, Other than the difference shown in the diagram, all other conditions were identical. 14. State one possible hypothesis that could be tested using these setups. [1] 15. What data should be collected in order to test the hypothesis stated in question 6 8? [1] 16. Describe one change that could be made in the investigation to improve it. [1]  © 2006 Gregory Arnold Study Guide The New Labs Page: 19 Lab Activity #3 The Beaks of Finches In this lab, students are introduced to the topic of evolution. The demonstrate how environmental conditions act as selecting agents. The species or members within a species with variations that make them better adapted to the environment survive and reproduce in greater number than those without the variations. These variations are called adaptations. Offspring will often have the same adaptations as the parents, and they too will have a better chance of survival as long as the environmental conditions remain the same. Charles Darwin is given credit of first advancing the theory of evolution. He called it natural selection, that is the environment or nature is the selecting agent. Charles Darwin arrived at this theory after studying many organisms including finches that inhabit the Galapagos Islands. Finches are small birds that are found in many areas of the world including Rockaway. The Galapagos Islands are located off the coast of South America. They contain many different species of finches, all descendants of the original finches that were probably blown to the islands by a storm. As the finches radiated (moved outward) to the various islands, they found a varied food supply. The finches that lacked the adaptations to get enough food died while the ones having the adaptations survived and produced offspring with similar adaptations. Over time, the finches evolved into many species that inhabited the islands today. The different species of finches found on the Islands today are arranged in the diversity wheel below. Evolution: What? — Why? — How? What: Evolution occurs when there is a change in the gene pool of a species. One organism does not evolve, the species evolves. Why: When a species is very well adapted to an unchanging environment, evolution is usually slow. (That is why many species of sharks, crocodiles and horseshoe crabs have remained virtually unchanged for millions of years. ) When an environment begins to change, the beneficial adaptations change also. Species must adapt or face extinction. In the past, most species, such as the many kinds of dinosaurs, have not been able to adapt to a changing environment and have become extinct. In the future, humans may face the same dilemma. How: Sexual reproduction (genetic recombination) and mutations are the driving forces of evolution. Sexual reproduction and mutations can cause the expression of different variations or adaptations in a given species. If the species is genetically diverse, and the environment begins to change, the species may survive because it may have the variation that will allow it to adapt to the changing environment. As the surviving members of the species reproduce, their offspring inherit these adaptations changing the gene pool of the species causing evolution. Here are all of the steps: 1. All species have variations. These variations are caused by combinations of genes and mutations. 2. There is a struggle for existence. Organisms are always competing for the available resources such as food, light, water, minerals, and space while avoiding to become the food of other organisms. 3. The organisms that are best adapted, the ones with the most favorable adaptations or variations, survive and produce offspring. 4. Overtime, the surviving organisms gene pool will change and evolution occurred. In the above example of the Galapagos finches, you might ask, Why so many different species developed from the original species? . The finches on each island was isolated from the other populations of finches on other islands and therefore they did not interbreed. Over time the gene pool became so different, they could no longer breed with each other even if they were on the same island. This indicates that new species were formed. (Definition of species All the organisms in a group that normally reproduce and produce fertile offspring. )  © 2006 Gregory Arnold Study Guide The New Labs Page: 20 Lab procedure: Students in this lab worked in pairs using regular household tools such as pliers, hair clamps, tweezers, and kitchen utensils as the beaks of finches. They competed for food beans that were placed on a paper plate in the center of the table (island). This lab was divided into three rounds: †¢ Round 1 — No inter-species competition. Students attempt to pick up as many small beans that was placed on a paper plate centered on a table (island) and transfer them to a cup. The idea was to acquire as much food as possible, one bean at a time, in 30 seconds. If the pair using the tool as a finch beak was unable to get the required amount of beans necessary to sustain life (an average of 13 beans), the finch was considered dead. If the finch died, the pair had a second chance by competing in round 2 on a different (table) island using larger seeds as food. The rules are the same. Either get enough food or become extinct. †¢ Round 2 — Inter-species competition. Students with different beaks competed and attempted to pick up as many beans that was placed on a paper plate centered on a table (island) between 2 pairs and transfer them to a cup. They acquired as much food as possible, one bean at a time, in 30 seconds. If the pair using the tool as a beak was unable to get the required amount of beans necessary to sustain life (an average of 13 beans), the finch was considered dead and out of the competition. The finch has become extinct. Note there were two major groups each with a number of subgroups in round 2. The tables with large seeds and the tables with small seeds. Only the pairs of students that collected an average of 13 beans moved to the third round which will again include the two major groups, but no subgroups. †¢ Round 3 — Inter-species competition. All of the pairs of students who survived the second round competed at once and attempted to pick up as many beans that was placed on a paper plate centered on a table (island) between all surviving finches and transfer them to a cup. Each finch acquired as much food as possible, one bean at a time, in 30 seconds. There were so many finches competing, most were not able to get the required average of 13 beans necessary to sustain life and therefore became extinct. If you cant follow the above description of this Laboratory exercise, here is the flow diagram. In this class, only 3 pairs of students have finches still alive. All others have become extinct. Only these three have the adaptations (tools) that allowed them to compete in the changing environment as they competed in all three rounds. Do you think the same results would occur if sunflower seeds was used instead of bean seeds?  © 2006 Gregory Arnold Study Guide The New Labs Page: 21 †¢ Explain why A, B and C were successful picking up the small seeds while D, E, and F were successful at picking up the larger seeds? Answer the Following Question: 1. Which finch populations would have a greater chance of survival if the insect populations of the Galapagos islands increased? Explain your answer. All students should have learned: 1. Evolution is the change in the number and/or type of genes in the gene pool of a population. A population is all of the organisms that normally mate with one another and produce fertile offspring. Evolution is accelerated when environmental conditions change, giving certain members of the population with favorable adaptations or structures an advantage for survival and therefore reproduction. The process of evolution includes: a. All species have variations. These variations are caused by combinations of genes and mutations. b. There is a struggle for existence. Organisms are always competing for the available resources such as food, light, water, minerals, and space while avoiding to become the food of other organisms. . The organisms that are best adapted, the ones with the most favorable adaptations or variations, survive and produce offspring. d. Overtime, the surviving organisms gene pool will change and evolution occurred. Variations are caused by: a. The normal mixing of genes during sexual reproduction. b. Mutations or a change in the DNA. If it occurs in the origina l gametes or in the sex organs, the mutation may be passed to the offspring. Competition only exists between different organisms occupying the same niche or function in the ecosystem. If two organisms have different food supplies, they do not compete with one another. The level of competition increases as the populations occupying the same niche increases and/or the food supply decreases. An environment with much food and many niches would have great biodiversity. Not only should there be many different species, but there should be many variations within each population because there is less struggling for survival. (Do you think that Toy poodles, Malteses, Yorkshire terriers and other small dogs would survive in the wild without humans? ) 2. 3. 4. 5. 6.  © 2006 Gregory Arnold Study Guide The New Labs Page: 22 Name: Topic 10C . The diagram below shows variations in beak sizes and shapes for several birds on the Galapagos Islands. 5. The different tools used during the beaks of finches lab represented (1) feeding adaptations in finches (2) nest construction adaptations (3) variations in seed size (4) variations in ecosystems 6. Beak structures differ between individuals of one species of bird. These differences most likely indicate (1) the pres ence of a variety of food sources (2) a reduced rate of reproduction (3) a large supply of one kind of food (4) an abundance of predators 7. A hawk has a genetic trait that gives it much better eyesight than other hawks of the same species in the same area. Explain how this could lead to evolutionary change within this species of hawk over a long period of time. In your answer, be sure to include an explanation of: †¢ competition within the hawk population [1] †¢ survival of various individuals in the population [1] †¢ how the frequency of the better-eyesight trait would be expected to change over time within the population [1] †¢ what would most likely happen to the hawks having the better-eyesight trait if they also had unusually weak wing muscles [1] Using information provided in the chart, identify two birds that would most likely compete for food in times of food shortage and explain why they would compete. [2] and 2. Even though the finches on the various Galapagos Islands require different biotic and abiotic factors for their survival, these finches would most likely be grouped in the same (1) species, but found in different habitats (2) kingdom, but found in different ecological niches (3) species and found in the same biosphere (4) population, but found in different ecosystems 3. Galapagos finches evolved partly due to (1) cloning and recombination (2) migration and selective breeding (3) mutation and asexual reproduction (4) variation and competition 4. In members of a bird species living on a remote island, the greatest number of beak variations in the population would most likely be found when (1) there is a high level of competition for limited resources (2) homeostasis is limited by a severe climate (3) they have a large and varied food supply (4) they are prey for a large number of predators  © 2006 Gregory Arnold Study Guide The New Labs Page: 23 Laboratory Activity #5 Diffusion Through a Membrane Background Information that you need to know: In this lab activity, students learned about the movement of molecules through the cell membrane. The cell membrane is a very important cell organelle. It separates the cell contents from the external environment, allowing specific chemical activities to occur within the cell. The cell membrane is said to be semipermeable, allowing only certain molecules to pass through it. Movement of molecules through the cell membrane can normally occur by two processes. They are 1. Active Transport Energy is expanded as molecules are moved from areas of low concentration to areas of greater concentration. Active transport will not be explored in this laboratory activity. 2. Diffusion Molecules move from areas of greater concentration to areas of lower concentration. Molecules diffuse due their random vibrations. The molecules move in a straight line until they strike another molecule, sending it outward. This process will cause concentrated molecules to spread out or move to areas of lower concentration. That is why everybody in a room will eventually smell a person who is wearing excessive perfume or cologne. (The molecules are jumping off of the person and spreading out to all corners of the room. ) Lab procedure: Part 1 Building a cell. Students followed the below procedure to build an artificial cell. One end of an eight inch dialysis tubing was tied closed. Dialysis tubing is made up of a plastic that has many little holes through which only small molecules can pass. The dialysis tubing represents the cell membrane. Water, glucose and starch was poured into the tubing. The other end of the dialysis tubing was tied closed. The cell was placed into a beaker half fulled with water. Iodine is added to the water in the beaker. Iodine, is an indicator of starch. Normally amber, iodine turns blue-black in the presence of starch. What had to happen for the cell to turn blue-black after 30 minutes?  © 2006 Gregory Arnold Study Guide The New Labs Page: 24 Based on the pictures and information above, label the contents and note the colors present in both the beaker and the cell at the beginning and at the end of the experiment. Indicators A indicator is a substance that is used to test for the presence of another substance. The indicator will react by changing color, fizzing, or reacting in some other obvious way. Two indicators used in this experiment are Iodine and Benedicts solution. Two common indicators. Indicator Solution Used * Blue color Benedicts Glucose Indicator Solution Amber-colored Iodine Starch Indicator Solution * Must be heated in a hot water bath. Testing the water in the beaker. Indicator Water in the Beaker At the beginning of Experiment At the end of Experiment Glucose Indicator solution (Benedicts) Starch Indicator Solution (Iodine) Materials Distilled Water Tested Glucose Starch Blue Amber Blue Blue-Black Orange Amber Blue Orange Amber Amber Conclusion of Part 1 In the Initial state diagram below, Iodine is indicated with the letter I. Using the letters S for starch, G for glucose and I for iodine, indicate the areas where each of these molecules are located in both diagrams. Which molecules passed through the membrane (dialysis tubing)? Explain your answer. Which molecules did not pass through the membrane? Explain your answer.  © 2006 Gregory Arnold Study Guide The New Labs Page: 25 Lab procedure: Part 2 — Diffusion of Water Across a Membrane (Osmosis). Osmosis is the diffusion of water across a membrane. It moves from areas of greater concentration of water to areas of lower concentration of water. Which way will the water move through the membrane in the three examples below? The effect of salt and distilled (pure) water on the cell. †¢ An onion cell in tap water under †¢ If this cell is exposed to salt high power of microscope looks water, water moves from like: inside the cell to the saltwater environment. This causes the contents of the cell to shrink. This can be clearly seen as the cell contents move away from the cell wall. If this cell is exposed to distilled (Pure) or even regular tap water, the water will enter the cell and cause the cytoplasm to expand and it will once again touch the cell wall. How to change the water without lifting the coverslip? All students should have learned: 1. Movement of molecules through a membrane by diffusion mostly depend on two factors: a. Size of molecule Small molecules can mo ve through the membrane while large molecules can not. Water, glucose, oxygen and carbon dioxide are small molecules and can move through the cell membrane by simple diffusion. Starch, proteins and DNA are large molecules and cannot move by diffusion through the membrane. b. Concentration of molecule: The molecules will move from areas of greater concentration to areas of lower concentration. Three cases concerning water are: Distilled water is 100% water. Distilled water will move through a membrane to a area where there is less than 100% water. 95% Water, 5% salt will draw water out of a cell, causing the cell to shrink because there is a greater concentration of water in the cell. (Putting salt on a slug will cause it to lose water and shrivel up. If the concentration of water is the same on both sides of the membrane, there is no net movement of water.  © 2006 Gregory Arnold Study Guide The New Labs Page: 26 Name: Topic 10D Base your answers to questions 4 through 6 on the information and diagram below. A student prepared a wet-mount slide of red onion skin and observed it under high power of a compound light microscope (view A). After adding a subs tance to the slide and waiting one minute, the student observed that there were changes in the cells (view B). 1. The diagram below represents a container of water and two different kinds of molecules, A and B, separated into two chambers by a membrane through which only water and molecule A can pass. On the diagram of the container below, indicate the distribution of molecules A and B after the net movement of these molecules stops. [2] Base your answers to questions 2 and 3 on the information below and on your knowledge of biology. Students prepared four models of cells by using dialysis tubing containing the same blue solution. Each of the model cells originally weighed 10 grams. They then placed each model cell in a beaker containing a different concentration of water. After 24 hours, they recorded the mass of the model cells as shown in the data table below. 4. Identify one substance that could have been added to the cells on the slide in view A that would make them resemble the cells observed in view B. [1] 5. Identify the specific substance that diffused to cause the change in appearance from view A to view B. [1] 6. In the box below, sketch how view B would appear when viewed under lower power of the same compound light microscope. [1] 2. Why did the model cell that was placed in 100% water increase in mass? [1] 7. Molecules A and B are both organic molecules found in many cells. When tested, it is found that molecule A cannot pass through a cell membrane, but molecule B easily passes through. State one way the two molecules could differ, that would account for the difference in the ability to pass through the cell membrane. [1] 3. What was the concentration of water in the original blue solution? State evidence in support of your answer. [1]  © 2006 Gregory Arnold Study Guide The New Labs Page: 27 . A student prepared a wet-mount slide of some red onion cells and then added some salt water to the slide. The student observed the slide using a compound light microscope. Diagram A is typical of what the student observed after adding salt water. Complete diagram B to show how the contents of the red onion cells should appear if the cell were then rinsed with distilled water for several minutes. [1] 11. Elodea is a pl ant that lives in freshwater. The diagram below represents one Elodea leaf cell in its normal freshwater environment. Predict how the contents of the Elodea cell would change if the cell was placed in saltwater for several minutes by completing the diagram, Elodea cell in saltwater below. Label the location of the cell membrane. [2] 9. The photos below show two red onion cells viewed with the high power of a compound light microscope. Describe the steps that could be used to make cell A resemble cell B using a piece of paper towel and an eyedropper or a pipette without removing the cover slip. [3] 12. An investigation was set up to study the movement of water through a membrane. The results are shown in the diagram below. 10. If vegetables become wilted, they can often be made crisp again by soaking them in water. However; they may lose a few nutrients during this process. Using the concept of diffusion and concentration, state why some nutrients would leave the plant cell. [1] Based on these results, which statement correctly predicts what will happen to red blood cells when they are placed in a beaker containing a water solution in which the salt concentration is much higher than the salt concentration in the red blood cells? 1) The red blood cells will absorb water and increase in size. (2) The red blood cells will lose water and decrease in size. (3) The red blood cells will first absorb water, then lose water and maintain their normal size. (4) The red blood cells will first lose water, then absorb water, and finally double in size. 13. State one factor that influences which molecules can pass through the cell membrane of a human cell. [1]  © 2006 Gre gory Arnold Study Guide The New Labs Page: 28

Proverbial Expressions Essay Example

Proverbial Expressions Paper Honesty is regarded as the best quality in a person. It always praised and admired . Without honesty we can not command respect from the people. No Pains No Gains This proverb has a very opt place in life of students because a student has to achieve his goal by hard work. Mans life is full of ups and downs. Life is not a bed of roses. People have to take pain in order to have gain in their life. It is proved by experience that the lazy people go down and hardworking people come up in life. A student who studies hard gets success in examination and also in life. If he is careless and neglect the work he ruins his life. A business man or a industrialist gets more profits if he works hard sincerely in his business. A farmer who works hard in his field has a very good cultivation. So people moving any path of life must sincerely work hard and take pains to get success in their life. Pain is necessary to enable us to enjoy pleasure. One cannot achieve success without getting hurt nor can one achieve anything unless one has experienced the bitterness of defeat. A Friend in need is a friend indeed All of us have friends but the truest friend is the one who is with us during the mime of adversities. Friendship is essence of life one can live without wealth. We will write a custom essay sample on Proverbial Expressions specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Proverbial Expressions specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Proverbial Expressions specifically for you FOR ONLY $16.38 $13.9/page Hire Writer But he cant live without friends. A True friendship is gods gift A friend who helps us in the time of necessity is a real sincere friend. A friend who leaves us when we are in trouble is not a true friend. Many people seem to be dear to us they talk to us in sweet words to get money and help from us. They are just like frogs that come to the pond or tank when there is water. When we have no money they desert us. Such friends are bad friends and they lead us in bad ways of our life. A true friend who supports us in all our joys and sorrows . He is like afire who provides warmth and supports during the time of difficulties. A True friend remains with us through thick and thin of our life. It is rightly said any ship can be drowned but not friendship in the sea of life. All that glitters is not gold Gold is a very costly and shining metal. It attracts many people because it is considered to be the most valuable metal the idea of the proverb is that a dazzling showy article need not to be valuable. Every thing that shines is not gold like wise everything that appears attractive should not be taken as gold. It is also true in the case of many people who appear to be pious and noble smiles sweetly to you may not be a genuine person. They are very shy and cunning one must be very careful while judging people and in choosing friends. Physical beauty is temporary just like the beauty of the rolled gold. Therefore we should not make a judgments on external appearances. In other words we can say that dont judge a book by its cover. Failure is the stepping stone to success The literary meaning of the proverb is that there is no success without defeat. One cannot become a hero without getting hurt nor one can achieve anything unless one has experienced the bitterness of defeat. Life is not a bed of roses. It is full of both pain and pleasure. The first attempt does not always lead to success. Man has to face failures. But one should not get disheartened . History shows several examples Mohammed Gain has to struggle and he struggled many times to conquer kingdoms . Mahatma Gandhi has faced many difficulties to achieve independence so failure is always a step to success , sometimes we try our best and work hard but still something may go wrong and our hard work is not rewarded but still we just try again and again until we succeed. Remember our attempts may fail but never fail to attempt Knowledge is power Or Pen is mightier than sword Knowledge gives everyone unlimited powers. Life is limited but knowledge is unlimited man has to make use of his limited time attaining maximum knowledge. It gives him great capacity to solve anything. People with knowledge rules the world and not the people with physical strength. A man of knowledge will be more respected than the man of wealth. People wrongly argue that money makes many things. But it cannot make a man without knowledge. So knowledge is power and it has been proved well in the modern days. The more time one spends in enhancing ones knowledge the more it produces greater results in all walks of life it gives a man confidence to face any situation in life. A man of knowledge worshipped throughout his life. Pride comes before a fall This is the modern version of an old proverb from the bible. Pride here means rash consent not justifiable self respect The meaning of this saying is that if you are too confident of your achievements and feel arrogant with no regards for others you are sure to face misfortune or fall into disgrace soon. It is peculiar that man becomes proud and behaves recklessly his fall has started one may be proud because of his riches and another may be of his power. They have to maintain throughout their life. There are many examples of rich people or powerful people or kings in the past who have fallen from their position because of their pride. In epics like Inhabitant and Ramadan Turnaround and Raven are the classic examples and their downfall was due to their pride. Pride goes before and shame follows after Time and tide wait for no man This proverb warns us that time will not wait for anyone. It keeps moving on ND there is no looking back. So we should make the most of our opportunities while they come. If we waste time and the opportunities we would regret it later. But by then it would be too late to do. Any opportunity only knocks once. The tides of sea goes on rising high and falling down according to the movements of the sun and the moon they do not wait for the orders for anyone. If we go on waiting for the proper tide, the movement may not arise at all. We must catch the time by fare lock. When opportunities knock our door we should utilize. An inch of gold will not buy a second of time Opportunities rarely comes and when hey come we should not leave them the value of time is very precious. Where there is a will there is a way This is a famous proverb if a man has a desire or intention the path is always open for him. Without a determined will we cannot solve anything. Will power is a strong force that can make even seemingly impossible things happen. The interest of the people alone will bring half of success of anything. So people can do anything well if there is a will to do it. The students also must have a strong will to get success in their examination in proper way.