Mock Exam 1 Biology 123 SI 1. Sodium and Lithium are two different elements, yet they react very similarly. What is the best explanation for this. a.

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1 Mock Exam 1 Biology 123 SI 1. Sodium and Lithium are two different elements, yet they react very similarly. What is the best explanation for this. a. They have the same number of electron shells. b. They have similar atomic numbers. c. They form isotopes with the same atomic mass. d. They have the same number of outer shell electrons. e. They have the same number of total electrons. 2. A fictional element normally has 14 protons, 17 neutrons, and 14 electrons. What could be an isotope of this fictional element? a. 14 protons, 17 neutrons, and 17 electrons. b. 15 protons, 17 neutrons, and 15 electrons. c. 14 protons, 200 neutrons, and 14 electrons. d. 17 protons, 17 neutrons, and 17 electrons. 3. If the atomic number of an element is 8 and the mass number is 16, what are the respective numbers of protons, neutrons, and electrons? a. 8,16,8 b. 16,8,16 c. 8,8,8 d. 16,24,16 e. 16,16,16 4. Calcium sulfate ionizes in water to form a calcium ion and a sulfate ion. If the calcium starts with two electrons in its outer shell, what is the charge on the sulfate ion? a. -1 b. -2 (it takes the 2 electrons from the calcium to fill its valence. ) c. 0 d. 1 e Which of the following is not a characteristic of life? a. Sexual reproduction b. Response to stimulus c. Growth and development d. Evolutionary adaptation e. None of the above 6. What role do van der Waals interactions play in biology? a. They involve the sharing of electrons between two atoms of equal electronegativity. b. They are too weak to play any important role. c. They are strong bonds that stabilize protein structure. d. They are weak bonds that help reinforce the structure of larger molecules. e. They involve the transfer of electrons from one atom to another. 7. Ionic bonds are a. Shared electrons between two atoms of equal electronegativity. b. Weak bonds that help stabilize protein structure. c. Sharing electrons between two atoms of unequal electronegativity. d. Attractions between ions of opposite charge. 8. If water was not polar, what would be the effect on global warming? a. There would not be much effect because changing the polarity of the water molecule does not change the chemical makeup of water.

2 b. The results would be much worse because the loss of the polar nature would cause water to lose its high specific heat and its ability to moderate temperature. c. The effects would only be slightly worse because other polar molecules like methane could take waters place in moderating the temperature. d. The effects would be worse because loss of the polar structure would cause waters specific heat to rise and would make water absorb more heat. 9. If cohesion did not exist a. A glass could not be slightly overfilled with water without spilling. b. Ions would not dissociate when added to water. c. Water would be able to dissolve oil. d. The surface of water would be able to support the weight of a human without breaking. e. None of the above. 10. You discover a cell and decide to characterize it. You find that it has a membrane bound nucleus, but it also has a cell wall and a centromere. What kind of cell could this be? a. Plant cell b. Animal cell c. Bacteria cell d. A new type of cell. 11. What causes the partial positive and partial negative charges of the water molecule? a. The high electronegativity of the Hydrogen atoms. b. The high electronegativity of the Oxygen atoms. c. The high electronegativity of the Water molecule. d. The low electronegativity of the Oxygen atom. e. Equal electronegativities of Oxygen and Hydrogen. 12. Molecules that repel contact with water are known as a. Hydrophobic b. Hydrophillic c. Hydrolytic d. Hydrogenic e. None of the above 13. Molecules that contain large amounts of carboxyl groups will be what in solution. a. Basic b. Acidic c. Neutral d. Highly unreactive e. High folding 14. Why is it useful for the cell membrane to be composed of lipids (hydrophobic molecules) when a majority of the cell is made of water? a. Hydrophobic molecules are needed in order to form a hydration ring around the cell. b. Hydrophobic molecules are needed to separate the two aqueous environments without dissolving. c. This helps the cell maintain the proper ph. d. This ensures that the cell can move easily. e. There is no use for lipids in the membrane. Evolutionarily this property is on its way out.

3 15. What type of macromolecule is this? a. Phospholipid b. Polysaccharide c. Steroid d. Protein e. Nucleic Acid 16. What do acids do in a solution? a. Decrease hydrogen ion concentration. b. Increase the specific heat of the solution. c. Increase the ph. d. Increase the hydrogen ion concentration. e. Both d and c. 17. A change in ph indicates a change in a. Positive ion concentration b. Negative ion concentration c. H+ ion concentration d. Solution concentration e. All of these. 18. Which nucleotides pair using three covalent bonds? a. Adenine and Cytosine b. Adenine and Guanine c. Guanine and Cytosine b. Adenine and Thymine e. Thymine and Guanine 19. Which atom is always associated with organic chemistry? a. Fluorine b. Hydrogen c. Carbon d. Nitrogen e. Both B and C 20. Regarding straight chain carbon compounds, which combinations of atoms would require at least one carbon carbon double bond? a. C2H6 b. C7H16 c. C3H4 d. C3O2H8 e. None of these. 21. Which functional groups are in all amino acids?

4 a. Carboxyl b. Carbonyl c. Amino d. Both A and C e. Both B and C 22. If you are studying a carbohydrate, what kinds of bonds are you studying? a. Ester linkages b. Glycosidic linkages c. Peptide bonds d. Phosphoanhydride bonds 23. What organelle is responsible for replacing proteins in the plasma membrane? a. The rough endoplasmic reticulum. b. The Golgi apparatus c. The rough and smooth endoplasmic reticulum. d. The smooth endoplasmic reticulum and the Golgi apparatus. e. The rough endoplasmic reticulum and the golgi 24. Which of the following functional groups will form a hydrogen bond with the oxygen atom of another functional group. a. Amino b. Carboxylic acid c. Sulfhydryl d. Hydroxyl e. All of the above 25. Which functional group is known for releasing a large amount of energy when its bonds are broken? a. Amino b. Phosphate c. Sulfhydryl d. Hydroxyl e. Carboxyl 26. What is true about the characteristics of the phosphate functional group? a. It donates negative charge to the molecule. b. It donates 2 negative charges when found in the middle of the molecule. c. It donates 1 negative charge when found at the end of the molecule d. All of the above are true. 27. What is an important function of ATP within the cell? a. ATP stores large amounts of energy within its carbonyl groups b. ATP releases energy by forming phosphate bonds c. ATP has the potential to react with water to release large amounts of energy. d. ATP is an important structural component to the cell membrane. e. ATP contains many methyl groups and is important in the control of gene expression. 28. This reaction is responsible for assembling monomers into polymers. a. Dehydration reaction b. Hydrolysis reaction c. Condensation reaction d. Monomerization reaction e. Both A and C

5 29. When you ingest certain large molecules, the cells lining the digestive tract take them in. How are they most likely taken in? a. Exocytosis b. Endocytosis c. Osmosis d. Active Transport e. Passive Transport 30. Plants store glucose as, and animals store glucose as. a. Starch, glycogen b. Cellulose, starch c. Glycogen, starch d. Glycogen, cellulose e. Starch, starch. 31. Proteins are long molecules made of monomers. a. Nucleic acids b. Amino acids c. Hydrocarbons d. Nucleotides e. Both A and D 32. What bonds hold triglycerides together? a. Phosphodiester linkages b. Ester linkages c. Glycosidic linkages d. Peptide bonds e. None of these. 33. What would be the immediate effect of removing all Fe from the body? a. The body would no longer have slight magnetic properties. b. Electric membrane potential in all cells would be disrupted. c. Hemoglobin would not be able to find oxygen and cells would die. d. Nothing would happen because Fe is not a major element. e. Nothing would happen because Fe is found in such a small amount within the body. 34. T/F: Minor elements are not as essential to life as major elements. False. 35. The hemoglobin protein has what type of structure? a. Primary b. Secondary c. Tertiary d. Quaternary e. All of the above. 36. The secondary structure of proteins does not involve a. The amino acid chain. b. Hydrogen bonding between the carboxyl and amino groups c. A helices and b - sheets. d. Hydrogen bonding between R groups. e. An N - terminis and a C terminis. 37. What is true of the hydrogenation reaction? a. Hydrogenation forms bonds between monomers to form polymers. b. Monomers must undergo the hydrogenation reaction to then be able to undergo the hydrolysis reaction to form proteins.

6 c. Hydrogenation can remove double bonds molecules. d. Hydrogenation involves the removal of hydrogen from a molecule to facilitate monomer binding. e. Hydrogenation is responsible for breaking apart polymers into monomers. 38. Which of the following best describes cell fractionation? a. The process by which electrons are fired at a metal coated sample to achieve a high resolution view of the sample s surface structure. b. The process by which cellular components homogenized, then viewed using a light microscope. c. The process by which a cell is frozen and the membrane is fractured between the lipid bylayer to view the protein composition. d. The process by which a cell s are broken apart and the components are separated based on differential centrifugation. e. None of the above. 39. Can a prokaryote produce its own proteins? a. It can because it contains DNA and ribosomes. b. It can because the golgi apparatus of prokaryotes can perform the function of the endoplasmic reticulum and assemble the proteins. c. It can because dehydration reactions occur freely in the cytoplasm of the cell. d. It can t because there is no endoplasmic reticulum to produce the proteins. e. It can t because there is no evolutionary need for such small cells to have their own proteins. 40. Cell walls of plants are composed of lipopolysaccharides. What part of the cell produces these components. a. DNA and enzymes within the cytosol b. Free ribosomes and enzymes within the cytosol c. Rough endoplasmic reticulum and the golgi apparatus d. Smooth endoplasmic reticulum and the golgi apparatus e. The golgi apparatus and ribosomes 41. Intestinal cells ensure that there is no material leaked from the intestinal tract into the body. What allows them to perform this function. a. Gap junctions b. Desmosomes c. Plasmodesmata d. Tight junctions e. The intestine is made of one gigantic cell. 42. If two cells have the same volume, but drastically different surface areas, the cell with the larger surface area is most likely to a. Be involved in high energy using tissues. b. Be involved in rapid substance uptake from the cellular environment. c. Be prokaryotic d. Have fewer proteins in the plasma membrane e. Have more than one nucleus. 43. Which of the following is a similarity between plant cell walls and the extracellular matrix (ECM) of animal cells. a. Both the cell wall and the ECM are completely external, independent, and separate from the plasma membrane. b. The plant cell wall and the ECM completely cover the surface of the plasma membrane

7 c. The plant cell wall and the ECM are composed of carbohydrates and proteins. d. Both the plant cell wall and the ECM rigidly maintain the shape of the cell. e. The plant cell wall and the ECM both act as a scaffold to hold cells together. 44. Which of the following is true regarding the cytoskeleton? a. Microtubules are the largest and most permanent components of the cytoskeleton. b. Microfilaments work to facilitate the movements of flagella and cilia. c. Microtubules provide tracts for the movements of organelles throughout the cell. d. Intermediate filaments are assembled and disassembled to allow cells to move via pseudopodia. e. None of the above. 45. Which cells are likely to have the most mitochondria? a. Muscle cells in the legs of a rabbit. b. Cells in the stem of a flower. c. Non-dividing cells in the skin of your finger. d. Non living cells in hair. e. Bacteria cells growing on an agar plate. 46. Which of the following statements about the fluid mosaic model is true? a. The fluid part of the model refers to the membrane in warm temperatures. The mosaic part refers to the membrane in colt temperatures. b. The fluid part of the model refers to the lateral movement of phospholipids in the membrane, and the mosaic part refers to the flip flopping of phospholipids in the membrane. c. The fluid part of the model refers to proteins dispersed in the membrane, and the mosaic part refers to the phospholipids of the membrane. d. The fluid part of the model refers to the phospholipids of the membrane, and the mosaic part refers to the membrane proteins. Mock Exam 1 Biology 123 SI e. The fluid part of the model refers to the cytoplasm of the cell, and the mosaic part refers to the cellular organelles. 47. What type of molecule would most likely participate in simple diffusion? a. Water b. Large nonpolar molecules c. Small nonpolar molecules d. Large polar molecules e. Small polar molecules 48. If a membrane that is freely permeable to glucose molecules and water, but impermeable to sucrose is placed in a solution that is 0.03M glucose and 0.04M sucrose, what will occur if the fluid inside the membrane is composed of 0.03M glucose and 0.02M sucrose? a. Water will diffuse inside the cell. b. Water will diffuse out of the cell. c. Glucose will diffuse into the cell. d. Sucrose will diffuse into the cell. e. Nothing, the system is isotonic. 49. The concentration of solute inside of an animal cell is 0.09M. To cause the cell to lyse, what type of solution would the cell need to be suspended in? a M b. 0.10M c. 0.09M d. 0.40M

8 e. 170mM 50. When you ingest certain large molecules, the cells lining the digestive tract take them in. How are they most likely taken in? a. Exocytosis b. Endocytosis c. Osmosis d. Active Transport e. Passive Transport 51. Which of the following nitrogenous base is a purine? a. Cytosine b. Thymine c. Adenine d. Uracil e. Kerosine