Which of these would be a valid hypothesis?

Which of these would be a valid hypothesis?.

Table of Contents

MULTIPLECHOICE SECTION INSTRUCTIONS: Read all instructions carefully. Please answer all questions. Each question is worth 0.5 points. The Multiple Choice section is worth 40 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.

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1. Which of these would be a valid hypothesis?

A) Human history is determined by a series of supernatural events.

B) Humans should help in the conservation of other animal species.

C) Humans are controlled by forces beyond our understanding.

D) Humans and bacteria share a common genetic code.

2. 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

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

I. State the problem

II. Analyze and interpret the data

III. Share the results with other scientists

IV. Develop a hypothesis

V. Design and perform an experiment to test the hypothesis

A) I → II → III → IV → V

B) III → I → V → II → IV

C) V →IV → III → II → I

D) I → IV → V → II → III

E) V → II → I → III → IV

4. 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 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.

B) In the control group, a chosen variable is altered in a known way. In the experimental 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 and control groups, two different variables are altered.

E) Experimental and control group experiments are identical and run in parallel to get repeatable results.

5. 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 prediction for new data suggesting new relationships among a range of natural phenomena

E) All of the above

6. You have formulated a hypothesis that light is not 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 seeds is placed in the dark under the same set of conditions. The control in the experiment is

A) seeds in the dark

B) seeds in the light

C) warm temperature

D) adequate moisture

E) germination rate

7. A newly discovered multicellular organism obtains food by digesting dead organisms. Such an organism is most likely a member of the kingdom .

A) Plantae

B) Fungi

C) Protista

D) Animalia

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

A) organelles

B) nuclei

C) DNA molecules

D) cells

E) plasma membrane

9. 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 150 women took a tablet containing 40 mg of Drug A for 90 days; 120 of this group decreased their blood levels of cholesterol by at least 10%. Another group of 150 women was given a tablet with no added Drug A for 90 days; 25 of these women decreased their blood levels of cholesterol by at least 10%.

Which of the following is the most reasonable and accurate conclusion based on results obtained in this experiment?

A) Drug A is good for women.

B) Drug A is found in the blood of women.

C) Women taking tablets supplemented with Drug A will show a decrease in cholesterol levels in the blood.

D) Women taking tablets supplemented with Drug A will show an increase in cholesterol levels in the blood.

E) Blood levels of cholesterol are not affected by oral supplementation of Drug A.

10. 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 polar

bear.

A) brown bear

B) sun bear

C) spectacled bear

D) giant panda

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11. 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

12. Relative to a pH of 3, a pH of 7 has a .

A) 400 times lower H+ concentration

B) 10,000 times lower H+ concentration

C) 4 times higher H+ concentration

D) 10,000 times higher H+ concentration

13. 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

14. Which component of the following reaction is the substrate, and which is the enzyme? sucrose + sucrase + water → sucrase + glucose + fructose

A) sucrose is the substrate, and sucrase is the enzyme

B) sucrase is the substrate, and sucrose is the enzyme

C) glucose is the substrate, and water is the enzyme

D) fructose is the substrate, and glucose is the enzyme

15. If one strand of a DNA double helix has the sequence AGTACTG, what will be the sequence of the complementary DNA strand?

A) GACGTCA

B) UCAUGAC

C) GUCAUGA

D) TCATGAC

E) impossible to tell from the information provided.

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

A) are found in animals, while plants are comprised of

B) have membrane-enclosed organelles, which are lacking in

C) have a plasma membrane, which is lacking in

D) have a nucleoid region, which is lacking in

17. A protist that contains contractile vacuoles in its cytoplasm most likely lives

A) in a marine environment

B) within the cells of another organism

C) in fresh water

D) where it can climb on vertical surfaces

18. Similar to the nucleus, chloroplasts and mitochondria are .

A) surrounded by two membranes

B) green

C) manufactured by the nucleolus

D) able to synthesize lipids

19. The endomembrane system includes .

A) ribosomes, lysosomes, vacuoles, and the endoplasmic reticulum

B) Golgi apparatus, ribosomes, vacuoles, and the endoplasmic reticulum

C) Golgi apparatus, lysosomes, ribosomes, and the endoplasmic reticulum

D) Golgi apparatus, lysosomes, vacuoles, and the endoplasmic reticulum

20. Which of the following processes could result in the net movement of a substance into a cell, if the substance is more concentrated within the cell than in the surroundings?

A) active transport

B) facilitated diffusion

C) diffusion

D) osmosis

21. If placed in tap water, an animal cell will undergo lysis, whereas a plant cell will not. What accounts for this difference?

A) expulsion of water by the plant cell’s central vacuole

B) the relative impermeability of the plant cell membrane to water

C) the relative impermeability of the plant’s nuclear membrane to water

D) the relative inelasticity and strength of the plant cell wall

22. 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) Many pathways are universal among living organisms.

D) 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.

Use the following information to answer questions 23-24 below.

A group of medical researchers recently investigated the effects of Drug X on lowering blood pressure in a group of hypertensive middle-aged men. The researchers did the following experiment and obtained the indicated results: One group of 150 men took a tablet containing Drug X for 3 weeks – 95 of these men decreased their blood pressure by at least 10% (three men from this group dropped out of the study). Another group of 150 men was given a tablet with no added Drug X for 3 weeks – 10 of these men decreased their blood pressure by at least 10% (two men from this group dropped out of the study).

23. 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

24. 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 men

B) Drug X is good for both men and women

C) Hypertensive men receiving Drug X for 3 weeks may show a decrease in blood pressure

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

E) Drug X has no effect on blood pressure

25. Plant cells .

A) do not need chloroplasts because their mitochondria meet their energy needs

B) have chloroplasts and mitochondria

C) use carbon dioxide but do not use oxygen

D) do not need mitochondria because their chloroplasts meet their energy needs

E) are prokaryotic

26. The ultimate source of the energy in food is .

A) the sun

B) producers

C) ATP

D) consumers

E) lipids and nucleic acids

27. What compound directly provides energy for cellular work?

A) C6H12O6

B) glucose

C) ATP

D) fat

28. 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 muscles contain large amounts of lactic acid following even mild physical exercise

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 muscle cells cannot split glucose to pyruvic acid

29. The disease gonorrhea has become increasingly resistant to treatment with antibiotics. What is the most likely scientific explanation?

A) The gonorrhea bacteria learned to avoid antibiotics.

B) The gonorrhea bacteria changed their genes when they sensed antibiotics.

C) Antibiotic-sensitive gonorrhea bacteria died out, but antibiotic-resistant gonorrhea bacteria have flourished and persisted.

D) The antibiotic increased the mutation rate in the gonorrhea bacteria.

E) both b and d.

30. 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 O2 and sugars and animals produce CO2 and H2O

D) Animals produce O2 and sugars and plants produce CO2 and H2O

31. Think of the cell as a factory, in which the organelles are specialized sites of production. All cells have a power plant, the mitochondrion. Plant cells have an additional “reactor” for the production of usable energy. It is called the

A) Golgi body

B) rough endoplasmic reticulum

C) central vacuole

D) vesicle

E) chloroplast

32. 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 C quinoa grew the tallest. A) A = 30 cm, B = 21 cm, C= 15 cm, D= 12 cm.

B) A = 22 cm, B = 11 cm, C= 25 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

33. 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

34. Homologous chromosomes .

A) carry genes controlling the same inherited characteristics

B) include only the autosomes

C) are a set of chromosomes that the cell received from one parent

D) carry the same versions of all genes

35. 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.

36. Genetic variation is accomplished by all but one of the following. Which is it?

A) the events of meiosis I

B) crossing over

C) independent assortment

D) the events of meiosis II

37. purebred plant that produces red seeds is crossed with a purebred plant that produces yellow seeds. The seeds of all of the offspring are red. Why?

A) The red allele is recessive to the yellow allele.

B) All of the offspring are homozygous red.

C) The red allele is dominant to the yellow allele.

D) The alleles are codominant.

38. This diagram of the human life cycle shows that .

A) meiosis produces a diploid zygote

B) meiosis produces haploid sperm and egg cells

C) fertilization produces a haploid zygote

D) a diploid zygote undergoes meiosis to produce an adult human

39. 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 = 2:1…phenotypic ratio = 50% attached earlobes: 25% free earlobes

B) genotypic ratio = 2:2 …phenotypic ratio = 2 attached earlobes: 2 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

40. couple has two female children. What is the probability that their next child will be male?

A) 25%

B) 50%

C) 33%

D) 67%

41. What is the key to recognizing 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) Pleiotropy occurs.

D) The trait varies along a continuum in the population.

Please read the following scenario to answer the following question.

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. Notice that some individuals (shown in gray) have a widow’s peak (W = dominant allele and w = recessive allele).

42. Janice’s genotype is .

A) Ww

B) WW

C) ww

D) WW or Ww

43. After replication, .

A) each new DNA double helix consists of two old strands

B) each new DNA double helix consists of one old strand and one new strand

C) each new DNA double helix consists of two new strands

D) one new DNA double helix consists of two old strands and the other new DNA double helix consists of two new strands

44. Translation converts the information stored in to .

A) DNA… RNA

B) RNA… a polypeptide

C) DNA… a polypeptide

D) RNA… DNA

45. 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

46. 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.

47. The mutation that resulted from her accident was probably .

A) an amino acid substitution

B) one that changed the triplet grouping of the genetic message

C) an error in translation

D) a loss in regulation of gene expression

48. 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

49. How are cells in different body tissues able to perform different functions?

A) The cells exhibit different patterns of gene expression.

B) Different chromosomes have been inactivated in different cells.

C) The cells contain different genes in their nuclei.

D) The mutations that have accumulated in the cells of the different tissues control functions.

50. Genetically modifying human cells may directly affect future generations.

A) intestinal

B) immune

C) gamete

D) somatic

E) B and D only

51. Ethical dilemmas raised by DNA technology and knowledge of the human genome include .

A) the potential for interfering in evolution

B) the safety of GM foods

C) the potential discrimination against people predisposed to certain diseases

D) all of the above

52. Which of the following are homologous?

A) the forelimb of a dog and the hindlimb of a cat

B) the forelimb of a dog and the forelimb of a cat

C) wings of a butterfly and wings of a sparrow

D) the mouth of a mosquito and the beak of a hummingbird

53. The similarity of the embryos of fish, frogs, birds, and humans is evidence of

A) analogy

B) common ancestry

C) genetic drift

D) convergent evolution

54. 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.

55. What does evolutionary fitness measure?

A) physical health of individuals

B) longevity

C) relative reproductive success within a population

D) population size and dispersion

56. Which of the following is most likely to decrease genetic variation?

A) directional selection

B) mutation

C) stabilizing selection

D) diversifying selection

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

A) protists

B) animals

C) protozoans

D) prokaryotes

58. 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

59. What type of interspecific interaction is described by a small fish that eats parasites from mouths of larger fish?

A) mutualism

B) herbivory

C) parasitism

D) pollination

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

A) Allopatric.

B) Microevolution.

C) Gene pool magnification

D) Macroevolution.

61. 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

62. Unique features of all vertebrates include the presence of a(n) .

A) scales

B) mammary glands

C) skull and backbone

D) amnion

63. 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

64. Water moves from land to the atmosphere through .

A) precipitation only

B) transpiration only

C) transpiration and evaporation

D) evaporation and precipitation

65. According to this evolutionary tree, approximately how many years ago did humans and orangutans share a common ancestor?

A) 1 million years ago

B) 7 million years ago

C) 12 million years ago

D) 20 million years ago

66. 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.

67. 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.

Please read the following scenario to answer the following two question(s).

Salmon eggs hatch in freshwater streams and, during the first year of their life, the young salmon migrate up to 1,000 km to the ocean. They spend varying amounts of time in the ocean (ranging up to five years), where they feed and grow, rapidly acquiring more than 95% of their biomass during this period. During the summer of their maturing year, they begin the long journey back to their home streams where they spawn. Although it is still uncertain how salmon navigate back to their spawning grounds, current hypotheses suggest that they have a highly developed sense of smell. At the spawning grounds, females use their tails to form a hollow cavity where they lay up to 8,000 eggs. The male fertilizes the eggs, and both adults typically die soon thereafter.

68. The physiological response that allows salmon to survive in fresh water, then in salt water, and then fresh water again is an example of .

A) a behavioral response

B) evolution

C) acclimation

D) an anatomical response

69. At different times in their lives, salmon can be found in all of the following

except .

A) a freshwater biome

B) a chaparral

C) the pelagic realm

D) an estuary

70. In an ideal, unlimited environment, what shape does a population’s growth curve most closely resemble?

A) S

B) J

C) ∧

D) ∪

71. 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.

72. Non-native species can have 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

73. 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) trophic

C) keystone

D) groundwater

74. An example of a mutualism, or +/+ relationship, is .

A) the relationship between corals and unicellular algae

B) cryptic coloration in frogs

C) herbivory

D) the relationship between Virginia’s warblers and orange-crowned warblers, which use some of the same resources

75. 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) competition

D) commensalism

76. On average, only about of the available energy in one trophic level is incorporated and stored as calories in the bodies of the next level up.

A) 10%

B) one-third C) 50%

D) 75%

77. The primary goal of conservation biology is to by .

A) catalog species; protecting federally listed endangered species

B) maximize the land set aside for wildlife; countering pollution

C) integrate human culture back into nature; maintaining genetic diversity within species

D) counter the loss of biodiversity; sustaining entire ecosystems and habitats

Use the following information to answer the following three questions.

Malaria is an infectious disease caused by a unicellular eukaryotic organism belonging to the genus Plasmodium. These eukaryotic organisms are transmitted from one person to another by the female Anopheles mosquito when it feeds on human blood. Within humans, the Plasmodium spp. destroy red blood cells and, without effective treatment, serious infections can lead to death. Currently, more than 400 million people are afflicted with malaria and between 1 to 3 million people die from it each year. Historically, a chemical compound called quinine has been used in developing effective drugs against malaria. In its natural environment, quinine is produced by certain trees native to South America. This chemical is synthesized in the outer layer of tree trunks and acts as an herbivore deterrent.

78. Based on the relationship between Plasmodium spp. and humans, these organisms would be considered .

A) parasites

B) hosts

C) producers

D) carnivores

79. Humans, mosquitoes, and Plasmodium together would be considered a(n)

A) population

B) community

C) ecosystem

D) population and community

80. Despite being used for many years, quinine-based drugs have not led to the eradication of malaria and currently there are mosquitoes that are resistant to the compound. Which of the following were likely important in the development of this resistance to quinine?

A) natural selection

B) mutualism

C) interspecific competition

D) biological magnification

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TERM or CONCEPT	Answer	Definition/Association
1. genetic drift		A. DNA molecule with attached proteins
2. chromosome		B. a haploid cell that combines with another haploid cell during fertilization
3. crossing over		C. a specific portion of a chromosome that contains information for a particular inherited trait
4. gamete		D. New species form in geographically isolated populations
5. gene		E. an interaction during meiosis in which chromatids exchange segments; results in genetic recombination
6. germ cell		F. a change in the gene pool of a population due to chance
7. sympatric speciation		G. the process in which ribosomes synthesize proteins using the mRNA transcript
8. mitosis		H. the synthesis of mRNA from a DNA template
9. translation		I. the type of cell division which is used in asexual reproduction and tissue growth and repair
10. transcription		J. the type of cell division responsible for gamete formation and sexual reproduction
11. allopatric speciation		L. a type of cell whose primary function is the formation of gametes for sexual reproduction
12. meiosis		M. New species form within populations in the same geographic area

MATCHING SECTION #1 (6 points)

MATCHING SECTION INSTRUCTIONS: Read all instructions carefully. Please answer all questions. Each question is worth 0.5 points. 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. microtubules		A. contain enzymes for intracellular digestion
2. chloroplasts		B. are primary cellular structures (or components) where proteins are assembled
3. Golgi bodies		C. package cellular secretions for export
4. DNA molecules		D. extract energy stored in carbohydrates; synthesize ATP; produce water and carbon dioxide
5. RNA molecules		E. synthesize subunits that will be assembled into two part ribosomes in the cytoplasm
6. central vacuoles		F. translate hereditary instructions into specific proteins
7. lysosomes		G. increase cell surface area; store substances
8. mitochondria		H. encode hereditary information
9. nucleoli		I. help distribute chromosomes to the new cells during cell division
10. ribosomes		J. convert light energy to chemical energy stored in the chemical bonds of glucose or starch

FILL IN THE BLANK SECTION (12 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 in your best answer on the Answer Sheet provided by your instructor.

1. You take a sample from a mysterious “blob” that has washed up on the shore of a nearby lake, and view the cells and their contents under a very high-resolution microscope. You can see that the cells are polygonal and you can identify the cell membrane, mitochondria, chloroplasts, the nucleus, and some Golgi bodies. You conclude that it must be a cell.

2. A resists changes in pH by accepting hydrogen ions from or donating hydrogen ions to solutions.

MATCHING SECTION #2 (5 points)

3. A dog gets many nutrients from its food including amino acids. What macromolecule can be built directly from amino acids?

4. selection can lead to a balance of two or more contrasting phenotypes in a population.

SHORT ANSWER SECTION

INSTRUCTIONS: Each question is worth two (2) points. Total points for this section is 12 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. Lithops, also called Stoneplants, are a type of plant that resembles little stones. These plants have the ability to blend in with their surrounding, which affords them protection from predators. If you were in an area containing Lithops, describe four characteristics you could identify to distinguish these plants from the stones they mimic.

2. A population of grasshoppers in the Kansas prairie has two color phenotypes, green and brown. Typically, the prairie receives adequate water to maintain healthy, green grass. Assume a bird that eats grasshoppers moves into the prairie. How will this affect natural selection of the grasshoppers? How might this change in a drought year?

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

4. When does a logistic population growth curve show the highest rate of growth? Why?

5. Soil pH determine what types of plants will grow the best. If soil is too acidic, lime can be added, and if it is too basic, peat moss can be added. You test your soil and find that its pH is 3.5, and you want to grow cucumbers, which prefer to grow in soils in the 7.5-

8.5 range. Would you add lime or peat moss to adjust your soil’s pH? Why?

6. The total solute concentration in a red blood cell is about 1-2%. Sucrose cannot pass through a red blood cell’s plasma membrane, but water and urea can. Osmosis will cause a red blood cell to expand the most when placed in which of the following solutions? Explain your answer.

A. a hypertonic sucrose solution

B. a hypotonic sucrose solution

C. a hypertonic urea solution

D. a hypotonic urea solution

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 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.

1. Before bringing a new drug to the marketplace, extensive testing is done on the drug by administering the drug to large numbers of individuals. Explain the importance of the scientific method, sample size, controls and variable in the drug evaluation process.

2. List the four “large molecules of life.” Identify their composition (building blocks) and structure, and describe one function they each perform in the cell.

3. How can you explain the occurrence of birth defects (caused by altered genes) in children and grandchildren of WWII atomic bomb victims, when the victims themselves were only mildly affected?

4. During the past 50 years, more than 200 species of insects that attack crop plants have become highly resistant to DDT and other pesticides. Based on what you have learned in this class regarding evolution, explain the rapid and widespread evolution of resistance. Now that DDT has been banned in the US, what do you expect to happen to levels of resistance to DDT among insect populations in the US? Why?

5. Water is crucial for life as we know it. One of the most important characteristics of water is its ability to act as a solvent. Explain why water is such a good solvent for polar and charged molecules.

6. Tobacco is the leading cause of preventable cancers today. In fact, there are very few known cancers for which smoking is not considered a risk factor. The relationship between cigarette smoking and disease has been studied for years. How can this problem be studied at many different levels of biological organization? Give some examples.

7. 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?

8. a. You are comparing two cells. One cell is very small, and the other cell is huge.

Under which conditions would you expect the larger cell to be more successful, or the small cell to be more successful? Give a specific explanation for your answer.

b. Explain why animal cells would be unable to exist without the presence of plant cells. Is this relationship reciprocal?

9. Two 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. Vincristine: damages the mitotic spindle

b. Adriamycin: binds to DNA and blocks messenger RNA synthesis

c. Compare and contrast tumor suppressor genes and proto-oncogenes. Which of these must mutate to produce cancer?

10. a. Cystic fibrosis is a recessive genetic disease. Two parents do not have cystic fibrosis; however, their child does. Fully explain how this could have happened using a Punnett square.

b. Hypophosphatemia (vitamin D-resistant rickets) is inherited as an sex-linked dominant 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 woman and a man with hypophosphatemia? Explain your answer using a Punnett square.

10. 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?

11. a. Explain why it takes about the same amount of photosynthetic productivity to produce 10 kilograms of corn as 1 kilogram of bacon.

b. Why do food chains and food webs typically have only three to five levels?

BONUS QUESTIONS (6 points)

Instructions: Type in the letter that represents your best answer to the questions below. Each question is worth 2 points. Total points for this section is 6 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, Dickey 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. Simon, Dickey and Reece, (Essential Biology)

C) According to Simon, Dickey and Reece (2013), vacuoles bud from the ER, Golgi apparatus, or plasma membrane.

D) Gel electrophoresis has many uses besides STR analysis. (Simon, Dickey & Reece, 2013)

E) An endospore is a thick-coated protective cell produced within a prokaryotic cell under harsh conditions (Essential Biology, Simon, Dickey & Reece).

F. None of the above.

2. 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) Madison, P. L. (2005). How exams affect heart rate. Journal of Cardiac Stress, 26(2), 168-180.

C) Portia Lee Madison, 2005, How exams affect heart rate, Journal of Cardiac Stress, Volume 26, (2), 168-180.

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

168.

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

26.2 (2005): 168-180.

F. None of the above.

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 authors’ surname or by organization (if there is no author), 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).

You have completed the exam.

Congratulations on completing BIO 103

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Which of these would be a valid hypothesis?