Unformatted text preview: Bio 311C - Exam I Introductory Biology I Fall 2007 Name: ________________________________________ EID:_________________ Select the best answer for the following questions and fill in the corresponding bubble on the answer sheet. Please answer the short answer and essay questions directly on your exam. Use PENCIL for the multiple choice. Use PEN for the short answer and essay (if you wish to be considered for regrade-ing). You have 50 minutes. Take a deep breath and Good Luck!! Multiple Choice = 1.5pts each 1. Which of the following is reflective of the phrase "the whole is greater than the sum of its parts"? a. high-throughput technology b. emergent properties c. natural selection d. reductionism 2. Which of the following statements best distinguishes hypotheses from theories in science? a. Theories are hypotheses that have been proved. b. Hypotheses usually are relatively narrow in scope; theories have broad explanatory power. c. Hypotheses and theories are essentially the same thing. d. Theories are proved true in all cases; hypotheses are usually falsified by tests. 3. What does the reactivity of an atom depend on? a. number of valence shells in the atom b. number of orbitals found in the atom c. number of electrons in each orbital in the atom d. presence of unpaired electrons in the outer valence shell of the atom 4. Nitrogen (N) is much more electronegative than hydrogen (H). Which of the following statements is correct about the atoms in ammonia (NH3)? a. Each hydrogen atom has a partial positive charge. b. The nitrogen atom has a strong positive charge. c. Each hydrogen atom has a slight negative charge. d. The nitrogen atom has a partial positive charge. 5. Tay Sachs disease is a result of a. substitution of one amino acid, which leads to misfolded hemoglobin b. mutation in a gene for a lysosome enzyme, which leads to the build up of lipids c. mutation in a fatty acid, which leads to the build up of lipids d. unregulated cell division, causing cancer 6. The ionic bond of sodium chloride is formed when a. chlorine gains an electron from sodium. b. sodium and chlorine share an electron pair. c. sodium gains an electron from chlorine. d. chlorine gains a proton from sodium. 1 Bio 311C - Exam I Introductory Biology I Fall 2007 7. Van der Waals interactions result when a. hybrid orbitals overlap. b. electrons are not symmetrically distributed in a molecule. c. molecules held by ionic bonds react with water. d. two polar covalent bonds react. 8. Which of the following is considered to be a weak molecular interaction? a. a covalent bond b. a van der Waals interaction c. a hydrogen bond d. both b and c 9. What do cohesion, surface tension, and adhesion have in common with reference to water? a. All increase when temperature increases. b. All are produced by ionic bonding. c. All are properties related to hydrogen bonding. d. All have to do with nonpolar covalent bonds. 10. Why does ice float in liquid water? a. The liquid water molecules have more kinetic energy and thus support the ice. b. The ionic bonds between the molecules in ice prevent the ice from sinking. c. Hydrogen bonds stabilize and keep the molecules of ice farther apart than the water molecules of liquid water. d. The crystalline lattice of ice causes it to be denser than liquid water. 11. Buffers are substances that help resist shifts in pH by a. donating H+ to a solution when they have been depleted. b. releasing OH- in basic solutions. c. accepting H+ when they are in excess. d. both a and c 12. Which property of the carbon atom gives it compatibility with a greater number of different elements than any other type of atom? a. Carbon has 6 to 8 neutrons. b. Carbon has a valence of 4. c. Carbon forms ionic bonds. d. both a and c 13. What is the reason why hydrocarbons are not soluble in water? a. The majority of their bonds are polar covalent carbon to hydrogen linkages. b. The majority of their bonds are nonpolar covalent carbon-to-hydrogen linkages. c. They are hydrophilic. d. They exhibit considerable molecular complexity and diversity. 2 Bio 311C - Exam I Introductory Biology I Fall 2007 14. Research suggests that side effects from Ritalin, the drug used to treat attention deficit disorder, may be caused by contamination of enantiomers, or molecules that a. have identical three-dimensional shapes. b. are mirror images of one another. c. lack an asymmetric carbon. d. differ in the location of their double bonds. 15. What important concept in biology does question 14 illustrate? a. transmission of information b. structure-function relationships c. emergent properties d. energy flow 16. Which is a basic functional group that can accept H+ and become positively charged? a. carbonyl b. sufhydryl c. phosphate d. amino 17. Polymers of polysaccharides, nucleic acids, and proteins are all synthesized from monomers by which process? a. connecting monosaccharides together (condensation reactions) b. the addition of water to each monomer (hydrolysis) c. the removal of water (dehydration reactions) d. ionic bonding of the monomers 18. A molecule with the chemical formula C16H32O16 is probably a a. carbohydrate. b. lipid. c. protein. d. hydrocarbon. 19. Humans can digest starch but not cellulose because a. the monomer of starch is glucose, while the monomer of cellulose is galactose. b. humans have enzymes that can hydrolyze the beta () glycosidic linkages of starch but not the alpha () glycosidic linkages of cellulose. c. humans have enzymes that can hydrolyze the alpha () glycosidic linkages of starch but not the beta () glycosidic linkages of cellulose. d. humans harbor starch-digesting bacteria in the digestive tract. 20. The 20 different amino acids found in polypeptides exhibit different chemical and physical properties because of different a. carboxyl groups attached to an alpha () carbon b. amino groups attached to an alpha () carbon c. side chains (R groups). d. alpha () carbons. 3 Bio 311C - Exam I Introductory Biology I Fall 2007 21. Which type of interaction stabilizes the alpha () helix and the beta () pleated sheet structures of proteins? a. nonpolar covalent bonds b. ionic bonds c. hydrogen bonds d. peptide bonds 22. The tertiary structure of a protein is the a. order in which amino acids are joined in a polypeptide chain. b. unique three-dimensional shape of the fully folded polypeptide. c. organization of a polypeptide chain into an helix or pleated sheet. d. overall protein structure resulting from the aggregation of 2 or more polypeptides 23. The R group or side chain of the amino acid serine is CH2-OH. The R group or side chain of the amino acid alanine is CH3. Where would you expect to find these amino acids in a globular protein in aqueous solution? a. Serine would be on the interior; alanine would be on the exterior of the protein b. Alanine would be on the interior; serine would be on the exterior of the protein c. Both serine and alanine would on the interior of the protein. d. Both serine and alanine would be on the exterior of the protein 24. What is the term used for a change in a protein's three-dimensional shape or conformation due to disruption of hydrogen bonds, disulfide bridges, or ionic bonds? a. stabilization b. destabilization c. renaturation d. denaturation 25. What is the term used for a protein molecule that assists in the proper folding of other proteins? a. tertiary protein b. chaperonin c. enzyme protein d. renaturing protein 26. Which of the following are nitrogenous bases of the pyrimidine type? a. cytosine and thymine b. thymine and guanine c. ribose and deoxyribose d. adenine and thymine 27. The difference between the sugar in DNA and the sugar in RNA is that the sugar in DNA a. is a six-carbon sugar and the sugar in RNA is a five-carbon sugar. b. has a six-membered ring of carbon and nitrogen atoms. c. can attach to a phosphate. d. contains one less oxygen atom. 4 Bio 311C - Exam I Introductory Biology I Fall 2007 28. Choose the pair of terms that correctly completes this sentence: Nucleotides are to ________ as ________ are to proteins. a. nucleic acids; amino acids b. amino acids; polypeptides c. genes; enzymes d. polymers; polypeptides 29. The volume enclosed by the plasma membrane of plant cells is often much larger than the corresponding volume in animal cells. The most reasonable explanation for this observation is that a. plant cells have a much higher surface-to-volume ratio than animal cells. b. plant cells are more highly convoluted (folded) plasma membrane than animal cells. c. plant cells contain a large vacuole that reduces the volume of the cytoplasm. d. animal cells are more spherical, while plant cells are elongated. 30. Prokaryotic and eukaryotic cells generally have which of the following features in common? a. a cell wall made of cellulose b. ribosomes c. flagella or cilia that contain microtubules d. linear chromosomes made of DNA and protein 31. In animal cells, hydrolytic enzymes are packaged to prevent general destruction of cellular components. Which of the following organelles functions in this compartmentalization? a. chloroplast b. lysosome c. central vacuole d. peroxisome 32. Dynein is a motor protein, which provides molecular motion in cells by interacting with what types of filaments? a. intermediate filaments b. microtubules c. actin d. keratin 33. Microfilaments are well known for their role in which of the following? a. ameboid movement b. formation of cleavage furrows c. contracting of muscle cells d. all of the above 34. The surface of an integral membrane protein would be best described as a. hydrophilic. b. hydrophobic. c. amphipathic. d. completely covered with phospholipids. 5 Bio 311C - Exam I Introductory Biology I Fall 2007 35. Which of the following statements is correct about diffusion? a. It is very rapid over long distances. b. It requires an expenditure of energy by the cell. c. It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration. d. It is an active process in which molecules move from a region of lower concentration to one of higher concentration. 36. A patient has had a serious accident and lost a lot of blood. In an attempt to replenish body fluids, distilled water, equal to the volume of blood lost, is transferred directly into one of his veins. What will be the most probable result of this transfusion? a. It will have no unfavorable effect as long as the water is free of viruses and bacteria. b. The patient's red blood cells will shrivel up because the distilled water is hypotonic compared to the cells. c. The patient's red blood cells will swell because the distilled water is hypotonic compared to the cells. d. The patient's red blood cells will shrivel up because the distilled water is hypertonic compared to the cells. 37. The movement of a substance across a biological membrane against its concentration gradient with the help of energy input is a. diffusion. b. active transport. c. osmosis. d. facilitated diffusion. 38. Which of the following characterizes the sodium-potassium pump? a. Sodium ions are pumped out of a cell against their gradient. b. The pump protein undergoes a conformational change. c. both a and b are correct d. neither a or b are correct Matching section (2 pt each) Choose one of the options below (a-e) that correctly describes the type of covalent bonds formed between monomers of the macromolecule listed. a) Glycosidic bonds b) Esters c) Peptide d) Phosphodiester e) Nucleic 39. Polysaccharides 40. Ribonucleic Acid 41. Proteins 42. Deoxyribonucleic Acid 6 Bio 311C - Exam I Introductory Biology I Fall 2007 Choose the correct description of the R groups shown below. Write your answer to the right of the box below. NOTE: each question WILL have two answers. Choose one answer from each column: A and B. A B polar hydrophobic nonpolar hydrophilic acidic basic 43. 44. 45. SHORT ANSWER (2pt each) Which three functional groups are represented in this structure? Please circle and label the functional groups. 46. 47. 48. 7 Bio 311C - Exam I Introductory Biology I Fall 2007 SHORT ANSWER: (2pts each, 20pts for this section) The year is 2047. A new single-celled life form, called a Barsoomian, has been recently discovered on Mars. You are an esteemed molecular biologist and have been asked to accompany the crew on a trip to the Martian base to study the new life form. Interestingly, the Barsoomian cells and cellular components are approximately the size of animal cells. One of your assistants is compiling an equipment list. 49. Which general type of microscope will you require to explore the smaller organelles and macromolecules in the cell? 50. Which general type of microscope will you require to observe living cells and larger organelles? You have arrived at the Martian base and have acquired samples of Barsoomians. 51. Your early observations have found that the Barsoomian has a plasma membrane and several membrane bound organelles. If this were an Earth organism, to which Domain (s) would it belong? 52. What technique would you use to isolate the various cellular organelles and how does this technique work? 53. After a series of experiments on the organism, you isolate four kinds of macromolecules. These macromolecules look quite similar to those in Earth organisms. Please label the structures below with the appropriate macromolecule category. ________ ____________ Somewhat surprisingly, further exploration into the Barsoomian cells determines that they are very closely related to Earth cells, both in structure and components. 54. After inspecting the local environment from whence the Barsoomian was isolated, you test the soil and according to your measurements, you find it contains very high levels of toxins. Is this observation qualitative or quantitative science? 55. Despite the toxicity to Barsoomians, they appear to be growing fine. Drawing from what you learned in Intro Biology, you rush back to the lab to study a particular organelle to see if it is playing a role in detoxifying the Barsoomian. What is this organelle? (please be as specific as possible). 8 Bio 311C - Exam I Introductory Biology I Fall 2007 56. The night temperatures on Mars can be quite cold. What 2 features do you hypothesize you will find in the Barsoomian's plasma membrane that allow the organism to adjust to very cold temperatures? 57. Careful analysis of the Barsoomian's DNA reveals something quite surprising. The DNA appears to be circular. Why is this unexpected? (Please provide a complete answer) 58. The energy and nutritional requirements of Barsoomians are light energy and inorganic compounds, respectively. Which of the following categories do these characteristics describe (photoautotroph, chemoautotroph, photoheterotroph, chemoheterotroph)? 59. ESSAY (3 pts): Distinguish fats vs oils by a) differences in molecular structure, b) appearance at room temperature, c) by whether they are more typically produced by plants or by animals. (OPTIONAL): The REPLACEMENT Question: (3pt) Please write a short answer question that you expected to see on this exam, but didn't appear, then answer it. Please note: The question and answer must be significantly different from questions asked above and definitions of words, True/False, multiple choice questions are not acceptable. Question: Answer: 9 ...
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This note was uploaded on 03/19/2008 for the course BIO 311C taught by Professor Satasivian during the Spring '08 term at University of Texas.
- Spring '08