Biology

School of Undergraduate Studies

Social, Behavioral, Mathematical, and Natural Sciences

FINAL EXAMINATION

INSTRUCTOR NAME: Kelly Austin

COURSE NAME: Introduction to Biology BIO 103

SECTION NUMBER: 6387

DUE DATE: Sunday, March 9, 2014, 11:59 PM

SUBMIT completed ANSWER SHEET to Assignment Folder Final Exam SUBMIT Essay Answers to Turnitin.com

IMPORTANT: STUDENT PLEASE ANSWER ALL QUESTIONS IN THE ANSWER SHEET DOCUMENT AND SUBMIT THE ANSWER SHEET TO YOUR ASSIGNMENTS FOLDER. FOLLOW ALL INSTRUCTIONS CAREFULLY.

DO **NOT**SUBMIT THIS TEST DOCUMENT FILE TO YOUR INSTRUCTOR.

GENERAL INSTRUCTIONS: This final examination is worth 200 points. There are 6 sections: Multiple choice (57 points), Fill-in-the-blank (15 points), Matching, (24 points), Short answer (24 points), Essay (80 points) and Bonus point (10 points) sections. Read all instructions carefully. *Do not leave any required questions blank. Make your best guesses.* **When answering questions for all sections, use the accompanying Answer Sheet. Submit the Answer Sheet document to your Assignment Folder on or before the due date.**

Page 1 of 23 © UMUC ALL RIGHTS RESERVED

Page 2 of 23 © UMUC ALL RIGHTS RESERVED

MULTIPLE CHOICE SECTION INSTRUCTIONS: Read all instructions carefully. Please answer all questions. Each question is worth 1 point. The Multiple Choice section is worth 57 points. **Do not enter your answers here.** Type in the letter you select as the best answer on the Answer Sheet provided by your instructor. 1. In the scientific method, a hypothesis ____________.

A) is a statement of fact B) can only be tested once C) is usually proven to be correct D) is a proposed explanation based on observations E) none of the above

2. What is the correct sequence of steps in the scientific method?

I. State the problem II. Analyze and interpret the data III. Develop a hypothesis IV. Share the results with other scientists V. Design and perform an experiment to test the hypothesis

A) III → I → V → II → IV B) I → III → II → IV → V C) V →IV → III → II → I D) I → III → V → II → IV E) V → II → I → III → IV 3. Which of these would be a valid scientific hypothesis?

A) Earthworms and humans share a common genetic code. B) Humans are controlled by forces beyond our understanding. C) Humans should help in the conservation of plant species. D) Human history is determined by a series of supernatural events.

4. You have formulated a hypothesis that “light is necessary for seed

germination.” To test your hypothesis, one set of maple seeds is placed in light with warm temperatures and adequate moisture. Another set of identical maple seeds is placed in the dark under the same set of conditions. The independent variable (IV) and the control in the experiment are:

A) IV: light; control: darkness B) IV: germination at warm temperatures; control: germination in the light C) IV: adequate moisture; control: light D) IV: seeds in the dark; control: rate of germination E) IV: light; control: germination rate

Page 3 of 23 © UMUC ALL RIGHTS RESERVED

5. To test a hypothesis about a given variable, experimental and control groups are tested in parallel. Which of the following best explains the dual experiments? A) In the control and experimental groups, two different variables are altered. B) In the experimental group, a chosen variable is altered in a known way. In the

control group, that chosen variable is not altered so a comparison can be made.

C) In the experimental group, a chosen variable plus all other variables are altered. In the control group, the chosen variable is altered; however, all other variables are held constant.

D) In the experimental group, that chosen variable is not altered so a comparison can be made. In the control group, a chosen variable is altered in a known way.

E) Control and experimental group experiments are identical and run in parallel to get repeatable results.

6. Which of the following can be considered definitions of “theory”?

A) A theory can be an explanation of scientific laws B) A theory is a widely accepted integrated explanation of numerous hypotheses,

each supported by a large body of observations and experiments C) A theory is a condensation and simplification of many data that previously

appeared unrelated D) A theory is a broad explanation that is supported by a great deal of evidence

and continues to inspire productive research. E) All of the above

7. Which of the following structures can perform all the activities required for life?

A) organelles B) nuclei C) plasma membrane D) cells E) DNA molecules

8. Relative to a pH of 6, a pH of 3 has a ______.

A) 300 times lower H+ concentration B) 1,000 times lower H+ concentration C) 3 times higher H+ concentration D) 1,000 times higher H+ concentration E) 3 times lower H+ concentration

Page 4 of 23 © UMUC ALL RIGHTS RESERVED

Use the following information to answer questions 9-10 below.

A group of medical researchers recently investigated the effects of Drug X on lowering blood pressure in a group of hypertensive middle-aged women. The researchers did the following experiment and obtained the indicated results: One group of 250 women took a tablet containing Drug X for 3 weeks – 195 of these women decreased their blood pressure by at least 10% (three women from this group dropped out of the study). Another group of 250 women was given a tablet with no added Drug X for 3 weeks – 67 of these women decreased their blood pressure by at least 10% (two women from this group dropped out of the study).

9. Which of the following is the most reasonable and accurate conclusion based on the results obtained in this experiment? A) Drug X is good for hypertensive women B) Drug X is good for both men and women C) Hypertensive women receiving Drug X for 3 weeks may show a decrease in

blood pressure D) Hypertensive women receiving Drug X for 3 weeks may show an increase in

blood pressure E) Drug X has no effect on blood pressure

10. Which of the following was the control group in this experiment?

A) the group of participants that received tablets containing Drug X B) the group of participants that received tablets that did not contain Drug X C) the number of participants in each group at the beginning of the experiment D) the number of participants in each group at the end of the experiment E) the amount of Drug X contained in the tablet

11. A substrate binds to an enzyme by interacting with amino acids in the_____.

A) dehydration reaction B) binding site C) hydrolysis site D) denaturation portal

12. What are the products in the following chemical reaction?

C6H12O6 + 6 H2O + 6 O2 6 CO2 + 12 H2O A) CO2 and H2O B) C6H12O6, H2O, and O2 C) O2 only D) C6H12O6, H2O, O2, CO2, and H2O

Page 5 of 23 © UMUC ALL RIGHTS RESERVED

13. Which component of the following reaction is the substrate, and which is the enzyme? lactose + lactase + water lactase + glucose + galactose A) glucose + galactose is the substrate, and water is the enzyme B) water is the substrate, and lactose is the enzyme C) glucose is the substrate, and water is the enzyme D) lactose is the substrate, and lactase is the enzyme E) lactase is the substrate, and glucose + galactose is the enzyme

14. In a cell, the endomembrane system includes ______. A) ribosomes, lysosomes, vacuoles, and the endoplasmic reticulum B) Golgi apparatus, ribosomes, vacuoles, and the endoplasmic reticulum C) lysosomes, Golgi apparatus, ribosomes, and the endoplasmic reticulum D) the endoplasmic reticulum, Golgi apparatus, and vesicles

15. If one strand of a DNA double helix has the sequence TGACTCG, what will

be the sequence of the complementary DNA strand? A) GACGTCA B) ACAUGAC C) ACTGAGC D) GUCAUGA E) impossible to tell from the information provided.

16. One difference between eukaryotic and prokaryotic cells is that eukaryotic

cells ______. A) are found in animals, while plant cells are comprised of prokaryotic cells. B) have a plasma membrane, which is lacking in prokaryotic cells. C) have a nucleoid region, which is lacking in prokaryotic cells. D) have membrane-enclosed organelles, which are lacking in prokaryotic cells.

17. Which of the following statements best describes the relationship between photosynthesis and respiration? A) Photosynthesis occurs only in plants and respiration occurs only in animals. B) Respiration is anabolic and photosynthesis is catabolic. C) Photosynthesis stores energy in complex organic molecules, while

respiration releases it. D) ATP molecules are produced in photosynthesis and used up in respiration. E) Photosynthesis produces energy, respiration uses energy.

18. What compound directly provides energy for cellular work?

A) C6H12O6 B) ATP C) glucose D) fat

Page 6 of 23 © UMUC ALL RIGHTS RESERVED

19. If placed in tap water, an animal cell will undergo lysis, whereas a plant cell will not. What accounts for this difference? A) the relative impermeability of the plant cell membrane to water B) expulsion of water by the plant cell’s central vacuole C) the relative inelasticity and strength of the plant cell wall D) the relative impermeability of the plant’s nuclear membrane to water

20. Plant cells ______. A) do not need chloroplasts because their mitochondria meet their energy needs B) are prokaryotic because they have cell walls C) use carbon dioxide but do not use oxygen D) do not need mitochondria because their chloroplasts meet their energy needs E) have chloroplasts and mitochondria

21. Which of the following is not a common feature shared by all metabolic pathways? A) Each pathway contains multiple intermediate products, and there are small

molecular differences between the intermediates. B) Each pathway is regulated to ensure the optimal use of resources and to

maintain the health of the cell. C) Each step within the pathway, or the conversion from one intermediate to the

next, is catalyzed by a nucleic acid with a reactive R group. D) Many pathways are universal among living organisms.

22. A child is born with a rare disease in which mitochondria are missing from certain skeletal muscle cells. Physicians find that the muscle cells function. Not surprisingly, they also find that ______. A) the muscle cells cannot split glucose to pyruvic acid B) the muscles contain large amounts of carbon dioxide following even mild

physical exercise C) the muscles require extremely high levels of oxygen to function D) the muscles contain large amounts of lactic acid following even mild physical

exercise 23. Which statement best describes the relationship between plants and

animals on earth? A) Plants produce O2 and sugars from CO2 B) Animals produce CO2 and H2O from sugars and O2 C) Plants produce CO2 and H2O, and animals produce O2 and sugars and D) Plants produce O2 and sugars and animals produce CO2 and H2O E) None of the above.

Page 7 of 23 © UMUC ALL RIGHTS RESERVED

24. The ultimate source of the energy in food is ______. A) producers B) the sun C) ATP D) consumers E) lipids and nucleic acids

25. A researcher planted seeds from four types of quinoa (Types A, B, C, and D) in a greenhouse to determine which type of quinoa grew the tallest. The plants were grown for 10 days and measured. The results are shown below. Choose the data set that demonstrates that Type B quinoa grew the tallest. A) A = 30 cm, B = 21 cm, C= 15 cm, D= 12 cm. B) A = 22 cm, B = 27 cm, C = 11 cm D= 4 cm C) A = 2 cm, B = 5 cm, C= 1 cm, D= 2 cm D) A = 30 cm, B = 12 cm, C= 28 cm, D= 1 cm E) A = 21 cm, B = 12 cm, C= 20 cm, D= 15 cm

26. A replicated chromosome consists of two ______ joined at the _____.

A) diploid genes; locus B) homologous chromosomes; crossing over point C) genomes; centrosome D) sister chromatids; centromere E) haploid chromosomes; fertilization point

27. Homologous chromosomes ______.

A) are both inherited from the female parent B) are a set of chromosomes that the cell received from one parent C) include only the autosomes D) carry the same versions of all genes E) carry genes controlling the same inherited characteristics

28. In meiosis, how does prophase I differ from prophase II?

A) During prophase I there is one diploid cell; during prophase II there are two haploid cells.

B) During prophase I chromosomes line up single file in the middle of the cell; during prophase II the chromosomes line up in double file in the middle of the cell.

C) During prophase I the chromosomes coil up; the chromosomes are not coiled up during prophase II.

D) In prophase I the sister chromatids are attached; in prophase II the sister chromatids are separated.

29. This diagram of the human life cycle shows that ______. A) meiosis produces a diploid

zygote B) meiosis produces diploid

sperm and egg cells C) fertilization produces a haploid

zygote D) a diploid zygote undergoes

meiosis to produce an adult human

E) None of the above. 30. A couple has two male children. What is the probability that their next child

will be female? A) 100% B) 25% C) 33% D) 50% E) 67% F) 0%

31. How can one recognize polygenic inheritance?

A) A mating between a homozygous and a heterozygous individual produces more than the expected number of offspring expressing the dominant trait.

B) All of the alleles of the gene for that trait are equally expressed. C) The trait varies along a continuum in the population. D) Pleiotropy occurs.

Page 8 of 23 © UMUC ALL RIGHTS RESERVED

Please read the following scenario to answer the following question.

Page 9 of 23 © UMUC ALL RIGHTS RESERVED

Widow’s peak, a pointed hairline on the forehead, is a genetic trait caused by a somatic dominant allele. It can be traced back through a family’s history using pedigree analysis. The pedigree shown here shows three generations of a family. Individuals shown in gray have a widow’s peak. (W = dominant allele and w = recessive allele)

32. Jonathan’s genotype is _______.

A) WW B) ww C) Ww D) WW or Ww E) impossible to tell

33. Translation converts the information stored in ______ to ______.

A) DNA… RNA B) DNA… a polypeptide C) RNA… DNA D) RNA… a polypeptide E) a polypeptide…. DNA

34. After replication, ______. A) each new DNA double helix consists of two new strands B) each new DNA double helix consists of two old strands C) one new DNA double helix consists of two old strands and the other new DNA

double helix consists of two new strands D) each new DNA double helix consists of one old strand and one new strand

35. What is the smallest number of nucleotides that must be added or

subtracted to change the triplet grouping of the genetic message? A) one B) two C) three D) four

Page 10 of 23 © UMUC ALL RIGHTS RESERVED

36. What is the ultimate source of all diversity? A) natural selection B) sexual recombination C) meiosis D) mutation

Please read the following scenario to answer the following two question(s). While working with cultured mouse cells, a researcher unknowingly treated the cells with a mutagen that causes the deletion or insertion of individual nucleotides in DNA. Subsequently, she isolated and cultured a single cell from this group. She noticed that the progeny of this cell were not producing a certain protein and that this affected their survival. 37. The mutation would be most harmful to the cells if it resulted in ______.

A) a single nucleotide insertion near the start of the coding sequence B) a single nucleotide deletion near the end of the coding sequence C) a single nucleotide in the middle of an intron D) deletion of a triplet near the middle of the gene

38. The mutation that resulted from her accident was probably ______.

A) an amino acid substitution B) a loss in regulation of gene expression C) one that changed the triplet grouping of the genetic message D) an error in translation

39. Why doesn’t your tongue grow hair?

A) because the genes for keratin have been deleted from the cells of your tongue

B) because different genes are expressed in different tissues C) because skin cells have extra DNA that encodes hair proteins D) because saliva prevents hair from growing E) because tongue cells contain enzymes that destroy the genes for hair

production 40. Which of the following are homologous structures?

A) the forelimb of a dog and the hindlimb of a cat B) the mouth of a mosquito and the beak of a hummingbird C) wings of a butterfly and wings of a sparrow D) the forelimb of a dog and the forelimb of a cat

Page 11 of 23 © UMUC ALL RIGHTS RESERVED

41. What does evolutionary fitness measure? A) physical health of individuals B) population size and dispersion C) relative reproductive success within a population D) longevity of a population

42. Which one of the following statements is true? A) Natural selection works on variation already present in a population. B) Natural selection works on non-heritable traits. C) Individuals evolve through natural selection. D) Organisms evolve structures that they need.

43. In the soil, some ______ convert nitrogen to a form that can be used by plants.

A) protists B) animals C) protozoans D) prokaryotes

44. What type of interspecific interaction is described by a small fish that eats

parasites from mouths of larger fish? A) mutualism B) herbivory C) pollination D) cannibalism

45. Antibiotic resistance is an example of what type of evolution?

A) Allopatric. B) Microevolution. C) Gene pool magnification D) Macroevolution.

46. Biomedical researchers study species as disparate as worms, fruit flies,

mice, zebrafish, or rhesus monkeys to understand our genes, and even our diseases. Why? A) Because these species have many inherited features that are very similar to

our own. B) Because these species are all prokaryotes, and therefore their genes are

99.9% identical to one another. C) Because they make up an interconnected food web when bacteria are added. D) Because rhesus monkeys gave us the Rh+ factor when they bit our ancestors.

Page 12 of 23 © UMUC ALL RIGHTS RESERVED

47. Consider the following food chain: A barn owl eats a shrew. This shrew has eaten a grasshopper. The grasshopper has eaten the leaves of a clover plant and a maple tree. What organisms are on the first trophic level? A) the barn owl B) the shrew C) the grasshopper D) the barn owl, the shrew and the grasshopper E) the clover plant and maple tree

48. Water moves from land to the atmosphere through _____.

A) precipitation only B) transpiration only C) transpiration and evaporation D) evaporation and precipitation

49. Which of the following is not a result of global warming?

A) changes in the breeding seasons of some species. B) decreasing sea levels. C) melting permafrost. D) shifts in the ranges of some species.

50. Which of the following are not examples of renewable resources?

A) Biofuels produced from plants or plant-derived by-products such as crop wastes.

B) Power supplied by human labor or livestock. C) Fertilizers made from animal manure and composted plants. D) Metal, cement, and glass, made using mined materials.

51. According to the logistic growth model, what happens to a population when the size of the population reaches carrying capacity? A) The growth rate remains unchanged. B) The growth rate begins to decrease in size. C) The population crashes. D) The growth rate is zero.

52. In an ideal, unlimited environment, what shape does a population’s growth

curve most closely resemble? A) S B) / C) ∧ D) ∪

53. Non-native species can influence biological communities by ______. A) preying upon native species B) competing with native species for resources C) reducing biodiversity D) doing all of the above

54. An example of a mutualism is ______.

A) herbivory B) cryptic coloration in snakes C) the relationship between unicellular algae and corals D) the relationship between voles and sparrows, which use some of the same

resources 55. Populations of two coexisting species are both tertiary consumers in a

community. What relationship may exist between these two organisms? A) predation B) mutualism C) commensalism D) competition E) meiosis

56. A _______ species exerts a particularly strong influence on an ecosystem

out of proportion to its size or abundance; its decline or extinction can cause a cascade of future extinctions within an ecosystem. A) commensal B) keystone C) trophic C) pelagic E) groundwater

57. Which consumer population in the system below would probably have the least energy available to it?

A) Clover B) Toad C) Aphid D) Ladybug E) Sunlight

Page 13 of 23 © UMUC ALL RIGHTS RESERVED

Page 14 of 23 © UMUC ALL RIGHTS RESERVED

************************************************************************************************ MATCHING SECTION #1 (12 points) MATCHING SECTION INSTRUCTIONS: Read all instructions carefully. Please answer all questions. Each question is worth 1 point. Match the level of hierarchy with its example in the table below. Type in the letter you select from the right column as the best answer on the Answer Sheet provided by your instructor.

Hierarchical Level

Answer Example

1. Atoms A. Human being; frog; dragonfly

2. Molecules B. nerve, muscle, connective, epithelial

3. Macromolecules C. all human beings

4. Organelles D. Great Barrier reef

5. Cells E. Stomach; Brain

6. Tissues F. Ca (calcium), Oxygen (O), Hydrogen (H), Nitrogen (N)

7. Organs G. flock of geese; school of fish

8. Organism H. lysosome, mitochondria, plasma membrane

9. Population I. neuron; erythrocyte

10. Species J. DNA, phospholipids

11. Community K. Water (H2O), Nitrate (NO3)

12. Ecosystem L. Grasses, shrubs, and trees growing in an old field

Page 15 of 23 © UMUC ALL RIGHTS RESERVED

MATCHING SECTION #2 (12 points) MATCHING SECTION INSTRUCTIONS: Read all instructions carefully. Please answer all questions. Each question is worth 1 point. Match the Definition/Association with the Term or Concept in the table below. Type in the letter you select from the right column as the best answer on the Answer Sheet provided by your instructor. TERM or CONCEPT Answer Definition/Association

1. Gamete A. These cells do not have a nucleus, but do have a plasma membrane, a cell wall, and a nucleoid region.

2. Eukaryotic plant cells B. These cells have a plasma membrane and a nucleus, but no chloroplasts or a cell wall.

3. Golgi bodies C. These cells contain chloroplasts and a nucleus.

4. All prokaryotes D. These cells have a plasma membrane and a cell wall, and either a nucleus or a nucleoid region.

5. Chromosome E. DNA molecule with attached proteins

6. Crossing over F. a haploid cell that combines with another haploid cell during fertilization

7. Eukaryotic animal cells G. the type of cell division responsible for gamete formation and sexual reproduction

8. Gene H. an interaction during meiosis in which nonsister chromatids exchange segments; results in genetic recombination

9. Mitosis I. help distribute chromosomes to the new cells during cell division

10. Plant and bacterial cells

J. package cellular secretions for export

11. Meiosis K. the type of cell division which is used in asexual reproduction and tissue growth and repair

12. Microtubules L. a specific portion of a chromosome that contains information for a particular inherited trait

Page 16 of 23 © UMUC ALL RIGHTS RESERVED

FILL IN THE BLANK SECTION (15 points)

INSTRUCTIONS: Provide the best answer for the items below. Each item is worth three (3) points. Please answer all questions in this section. Type your best answer on the Answer Sheet provided by your instructor. 1. ________ is the total amount of living organic materials or group of organisms

within an ecosystem. 2. Enzymes are biological ________ that mediate the conversion of substrate to

product, by lowering the activation energy of the reaction. 3. A ________ bond is an interaction between a partially positive hydrogen atom

and a partially negative atom with unshared (lone) pair of electrons. 4. _______ is the stage of mitosis where new nuclear envelopes form around the

separated chromosomes at each pole of the cell, the chromosomes unfold back into chromatin, nucleoli reappear, and the cell continues to elongate.

5. ________ is the movement of a substance across a biological membrane against

its concentration gradient, aided by specific transport proteins and requiring input of energy (often ATP).

SHORT ANSWER SECTION INSTRUCTIONS: Each question is worth four (4) points. Total points for this section is 24 points. Complete 6 questions in this Short Answer Section. **Do not enter your answers here.** Type your answers into the Answer Sheet provided by your instructor. 1. Soil pH determine what types of plants will grow the best. If soil is too acidic, lime can be added to the soil, and if it is too basic, peat moss can be added to the soil. You test your soil and find that its pH is 2.8, and you want to grow oaks, which prefer to grow in soils in the 6.0-7.5pH range. Would you add lime or peat moss to adjust your soil’s pH? Why? 2. When does a logistic population growth curve show the highest rate of growth? Why?

3. DNA and RNA are similar yet distinct components of the cell. Describe four differences between RNA and DNA with respect to their chemical composition, structure, and or function. Describe in detail each characteristic you chose in your response.

Page 17 of 23 © UMUC ALL RIGHTS RESERVED

4. You are setting up a blood cell osmosis lab for a group of students and prepare three solutions: 0.05% salt; 1.2% salt, and 65% salt. Unfortunately, prior to lab, the labels fall off the solution bottles and are thrown away, and the bottles are mixed up. You tell the students that they will deduce the identity of each solution by interpreting the data they collect. Students place red blood cells into each of the three solutions; wait for 10 minutes, and then observe the size and shape of the red blood cells under the microscope. The internal solute concentration of red blood cells is approximately 1% salt. The students’ observations are summarized below in Table 1: Table 1. Condition of red blood cells in three types of solutions. Solution 1

0.05% salt Solution 2 1.2% salt

Solution 3 65% salt

Size and Shape of Red Blood Cells

Crenated Shriveled up Crinkly Tiny Spiny

Swollen; some have burst open Puffy Balloon-like Like a globe

Round and flat Disc-shaped Like a doughnut with a solid flat middle Like a soup plate

Based on the students’ data, which solution is which? Explain your answer. A. Solution 1 = isotonic; Solution 2 = hypertonic; Solution 3 = hypotonic B. Solution 1 = isotonic; Solution 2 = hypotonic; Solution 3 = hypertonic C. Solution 1 = hypertonic; Solution 2 = hypotonic; Solution 3 = isotonic D. Solution 1 = hypertonic; Solution 2 = isotonic; Solution 3 = isotonic 5. The brown bracts of the plant Monotropsis odorata resemble leaf litter, which affords them protection from predators. Describe four characteristics of life you could identify to distinguish these plants from the dead leaves they mimic.

6. A population of snails with either striped or monochrome (one-color) shells has become newly established in a new region. The snails are prey for birds that crack the snails open with their beaks, eat the soft bodies, and leave the shells. Researchers monitoring the area record the number of live snails and broken shells. Their data is summarized below:

Striped shells Monochrome shells Number of live snails 264 296 Number of broken snail shells 486 377 Total 750 673

a) Based on these data, which snail form is more subject to predation by birds? b) Predict how the frequencies of striped and monochrome individuals in the

population might change over the generations under predation pressure. c) Over time, a prolonged drought in the area favors snails that develop thicker,

harder shells that protect their juicy bodies from desiccation. What will happen to the birds that depend on the snails for food?

Page 18 of 23 © UMUC ALL RIGHTS RESERVED

ESSAY SECTION ESSAY. Eight Essays @ 10 points each. Total points for this section is 80 points. INSTRUCTIONS: Choose and answer eight (8) essay questions from the list below. The full number of points will be awarded for accurate and complete answers. Partial credit will be given for less than thorough answers, so answer eight essay questions from the list. If you answer more than eight, I will grade the first eight that you answer. Remember to address all parts of a question. Do your own work in your own words. Submit your essay answers to Turnitin.com. **Do not enter your answers here.** Type your answers into the Answer Sheet provided by your instructor. Indicate the number of the question you selected on the answer sheet.

Question 1. A group of medical researchers recently tested the effects of a cholesterol-lowering medication, Drug A, on women who had high blood levels of cholesterol. The researchers did the following experiment and obtained the indicated results. One group of 160 women took a tablet containing 42 mg of Drug A for 90 days; 130 of this group decreased their blood levels of cholesterol by at least 10%. Another group of 160 women was given a tablet with no added Drug A for 90 days; 27 of these women decreased their blood levels of cholesterol by at least 10%. a) What is the independent variable in this experiment? b) What is the dependent variable in this experiment? c) What is the control? d) What is the sample size? e) What is the most reasonable and accurate conclusion based on results obtained in this experiment?

Question 2. A dead opossum collected by animal services was collected from a

homeowner’s basement. The forensics lab wants to determine the types of food it ate just before it died. Stomach analysis reveals the following types of molecules: glucose, argentine, glycerol, galactose, glutamine, cysteine, and long chains of carbon with –COOH at one end. The lab determines that the opossum ate three out of the four types of large biological molecules. Which three types of large molecules did the opossum eat? Explain.

Question 3. How can the relationship between hepatitis B virus and liver cancer be

studied at different levels of biological organization? Give at least three examples.

Page 19 of 23 © UMUC ALL RIGHTS RESERVED

Question 4. Compare and contrast mitosis and meiosis. a) What is the function of each? b) How many cells are produced, and are they haploid or diploid? c) Are the products genetically identical to the parent cells? d) Gametes are supposed to be haploid. What two outcomes are the result of nondisjunction? e) How do genetic birth defects (caused by altered genes) appear in children and grandchildren of WWII atomic bomb victims, when the bombing victims themselves were only mildly affected? What specific cells must have been affected?

Question 5. a) The cells of your body are surrounded by water. The plasma

membrane of these cells is made of many nonpolar molecules. What would happen to these cells if the plasma membrane was made of mainly polar molecules? Why? Explain your answer. b) Many scientists feel that finding water on a planet is essential for the existence of extraterrestrial life. Why? Describe at least three specific properties of water that make it so critical for life.

Question 6. Predict what will happen in the following experiment based on what

you know about photosynthesis and cellular respiration. a) You place a plant alone in a covered airtight container in the presence of

sunlight. Assume a watering system is provided. What will happen to the plant (will it live or die), and why?

b) You place a butterfly alone in a covered airtight container with nectar and a source of water. What will happen to the butterfly, and why?

c) You place a plant and a butterfly together in a covered airtight container with food, water, and sunlight. What will happen to the plant and the butterfly, and why?

Question 7. a) Compare and contrast sympatric and allopatric speciation and give

an example of each. b) With the ability to clone animals, such as endangered species, their population numbers can be increased in a short time. How would cloning a population of animals from a one or a few individuals impact these populations from the perspective of the gene pool and genetic variability?

Page 20 of 23 © UMUC ALL RIGHTS RESERVED

Question 8. Examples of chemotherapeutic drugs (used to treat cancer) and their cellular actions are given below. Explain why each drug could be fatal to a cancer cell. a) Drug A: masquerade as the normal building blocks of RNA and DNA b) Drug B: damages the mitotic spindle c) Drug C: binds to DNA and blocks messenger RNA synthesis d) Compare and contrast tumor suppressor genes and proto-oncogenes. Which

of these must mutate to produce cancer? Question 9. a) A genetic disease (designated by allele R) is inherited as a sex-

linked recessive trait. The relevant gene is found on the X chromosome. What is the expected genotypic ratio and phenotypic ratio of a cross between a homozygous recessive male and a homozygous dominant woman? Explain your answer using a Punnett square. b) Huntington’s disease is a somatic dominant genetic disease. Two parents are carriers for Huntington’s; however, their child does not have the disease. Fully explain how this could have happened using a Punnett square.

Question 10. a) Why do food chains and food webs typically have only three to five levels?

b) Assuming typical efficiency of energy transfer from one trophic level to the next, describe how 1,000 calories in producer biomass might be converted to carnivore body mass. How many calories will the carnivore receive from the original 1,000 calories? Explain.

Question 11. a) The logistic model gives us some guidance about how much to take from a harvestable population. Ideally, we would like to maintain the population at a stable level over time, and we would like to be able to take as large a harvest as we can without depleting the population. Imagine that a goose population adjacent to an airport is harvested very heavily for several years until its size is just 10% of the carrying capacity. What level of harvest (high or low) could be sustained without decreasing the population further? Explain your answer.

b) Imagine that no hunting is allowed and the population grows nearly to its carrying capacity. Now that the geese are so abundant, managers decide to allow an annual harvest. What level of harvest (high or low) could be sustained while keeping the population level constant capacity? Why?

BONUS QUESTIONS (10 points) Instructions: Type in the letter that represents your best answer to the questions below. Each question is worth 1 points. Total points for this section is 10 points; no penalty for incorrect answers. 1. Which of the following demonstrates the correct use of a parenthetical in-

text citation formatted in APA style? A) According to Simon and Reece, roughly half the corn crop in the U.S. is

genetically modified. (2013). B) Glycolysis produces O2 even in the absence of oxygen. Williams, (Essential

Biology, 1987) C) Gel electrophoresis has many uses besides STR analysis. (Hampton &

McDonnell, 2014) D) According to Roberts (2012), chlorophyll pigments a and b absorb different

wavelengths of light. E) An endospore is a thick-coated protective cell produced within a prokaryotic cell

under harsh conditions (Concepts in Fungi, Morgan, Cincinnati, New York). F. None of the above. 2. Using the branching tree of life for bears depicted in the accompanying

figure, choose from among the following bear species the one that is most closely related to the sun bear.

A) spectacled bear B) sloth bear C) polar bear D) giant panda E) none of the above

Page 21 of 23 © UMUC ALL RIGHTS RESERVED

Page 22 of 23 © UMUC ALL RIGHTS RESERVED

3. For APA format, the reference sources at the end of your paper should be

A) numbered in the order in which they are cited in the text of the paper. B) listed under separate subheadings according to the type of source (book, film

journal article, website, etc.). C) listed first by sources with authors, then by those without authors, then by those

without publication years. D) in alphabetical order by title, regardless of the type of reference (book, film journal

article, website, etc.). E) in order of publication year (oldest references first, then the most recent last). F) None of the above. 4. A contractile vacuole is an organelle in single-celled protists that regulates

osmosis within the cell by collecting water that diffuses into it, and expelling it. In what environment would a protist with a contractile vacuole most likely live? A) in the atmosphere B) within the cells of another organism C) in fresh water D) where it can climb on vertical surfaces

5. Which of the following does not contribute to genetic variation?

A) the events of meiosis I B) the events of meiosis II C) independent assortment D) crossing over

6. A purebred plant that produces purple seeds is crossed with a purebred

plant that produces white seeds. The seeds of all of the offspring are white. Why? A) The purple allele is recessive to the white allele. B) All of the offspring are homozygous purple. C) The purple allele is dominant to the white allele. D) The alleles are codominant.

7. Which of the following is most likely to decrease genetic variation? A) directional selection B) mutation C) stabilizing selection D) diversifying selection

Page 23 of 23 © UMUC ALL RIGHTS RESERVED

8. Attached earlobes are recessive to free earlobes. What genotypic and phenotypic ratios are expected when an individual with attached earlobes mates with an individual heterozygous for free earlobes?

A) genotypic ratio = 2:2 …phenotypic ratio = 2 attached earlobes: 2 free earlobes

B) genotypic ratio = 2:1…phenotypic ratio = 50% attached earlobes: 25% free earlobes

C) genotypic ratio = 1:2:1…phenotypic ratio = 1 attached earlobes: 2: semi- detached earlobes: 1 free earlobes

D) genotypic ratio = 3:1…phenotypic ratio = 1 attached earlobes: 3 free earlobes

9. Which of the following journal articles is documented correctly in APA style? A) Madison, Portia Lee. “How exams affect heart rate.” Journal of Cardiac Stress.

26.2 (2005): 168-180.

B) Journal of Cardiac Stress. (2005). How exams affect heart rate. P. L. Madison. P.

168.

C) Portia Lee Madison, 2005, How exams affect heart rate, Journal of Cardiac

Stress, Volume 26, (2), 168-180.

D) Madison, P. L. (2005). How exams affect heart rate. Journal of Cardiac Stress,

26(2), 168-180.

E) Madison, Portia L. (2005). “How exams affect heart rate.” Journal of Cardiac

Stress. 26.2 (2005): pages 168-180.

F. None of the above.

10. The _____ evolved from small prokaryotes that established residence

within other, larger prokaryotes. A) vacuoles and lysosomes B) Golgi apparatus and endoplasmic reticulum C) centrioles and ribosomes D) mitochondria and chloroplasts

You have completed the exam.

Congratulations on completing BIO 103

Order now and get 10% discount on all orders above $50 now!!The professional are ready and willing handle your assignment.

ORDER NOW »»