front 1 Which of the following statements about cells is correct? | back 1 Both prokaryotic and eukaryotic organisms are made up of cells. |
front 2 A cell lacking which of the following structures is most likely to be a prokaryote? | back 2 Nuclear membrane |
front 3 Which of the following statements is true regarding the complexity of biological systems? | back 3 Knowing the function of a component of a living system can provide insights into the structure and organization of the living system. |
front 4 Which of the following statements about genetic information is correct? | back 4 All forms of life employ the same genetic code |
front 5 Which of the following is an example of genetic variation? | back 5 One sibling has brown eyes, the other has green |
front 6 About 20-25% of the 92 natural elements are known to be essential to life. Which four of these elements make up approximately 96% of living matter? | back 6 carbon, hydrogen, nitrogen, oxygen |
front 7 A controlled experiment is one in which | back 7 there are at least two groups, one of which does not receive the experimental treatment. |
front 8 What is the difference between covalent bonds and ionic bonds? | back 8 Covalent bonds involve the sharing of electrons between atoms: ionic bonds involve the electrical attraction between atoms. |
front 9 Under which of the following conditions will an atom be the most stable? | back 9 when all of the electron orbitals in the valence shell are filled |
front 10 How is a covalent bond formed? | back 10 two atoms share one electron |
front 11 Which of the following is a hydrophobic material? | back 11 table salt |
front 12 The partial negative charge in a molecule of water occurs because | back 12 the electrons shared between the oxygen and hydrogen atoms spend more time around the oxygen atom nucleus than around the hydrogen atom nucleus |
front 13 Which of the following properties of water is responsible for the formation of raindrops? | back 13 cohesion property |
front 14 A slice of pizza has 500 kcal. If we could burn the pizza and use all the heat to warm a 50-L container of cold water, what would be the approximate increase in the temperature of the water? (Note: A liter of cold water weighs about 1 kg.) | back 14 10°C |
front 15 Which of the following functional groups is hydrophobic in nature? | back 15 methyl |
front 16 ATP is necessary for life because | back 16 it is the principle energy carrying molecule in a cell |
front 17 Choose the Figure that depicts polymer synthesis. Figure 1 = Away from the molecules Figure 2 = Toward the molecules | back 17 Figure 1 |
front 18 A polysaccharide is a polymer made up of which kind of monomers? | back 18 simple sugars |
front 19 The tertiary structure of a polypeptide is the | back 19 overall three-dimensional shape of a fully folded polypeptide. |
front 20 The tertiary structure of a polypeptide is the | back 20 overall three-dimensional shape of a fully folded polypeptide. |
front 21 Which of the following statements about proteins is true? | back 21 Some proteins form a complete 3-D structure only when they interact with their targets. |
front 22 Which of the following ratios of nucleotides is constant for DNA? | back 22 A + G= T + C |
front 23 Which structure is not part of the endomembrane system? | back 23 chloroplast |
front 24 Which structure is common to plant and animal cells? | back 24 mitochondrion |
front 25 Which of the following statements best describes one major difference between prokaryotic cells and eukaryotic cells? | back 25 Eukaryotic cells have membrane-bound organelles, while prokaryotic cells do not. |
front 26 Which of the following parameters is most likely to limit the maximum size of a cell? | back 26 the ratio of surface area to volume of cytoplasm |
front 27 Tay-Sachs disease is a human genetic abnormality that results in cells accumulating very large, complex, undigested lipids. Which cellular organelle must be defective in this condition? | back 27 the lysosome |
front 28 Disruption of nuclear pore complexes in a eukaryotic cell will most likely interfere with the transport of which of the following molecules out of the nucleus? | back 28 mRNA |
front 29 Examination of a cell by transmission electron microscopy reveals a high density of ribosomes in the cytoplasm. This observation suggests that the cell is actively producing large amounts of which of the following molecules? | back 29 proteins |
front 30 Which of the following organelles often occupy the majority of the volume of a plant cell? | back 30 central vacuole |
front 31 Which of the following organelles is primarily responsible for the production and modification of polysaccharides that will be secreted? | back 31 Golgi apparatus |
front 32 A newly synthesized protein destined for secretion from a eukaryotic cell will generally follow which of the pathways listed below? | back 32 rough ER -> Golgi -> transport vesicle - plasma membrane |
front 33 An organelle in a newly discovered cell contains thylakoids, DNA, and ribosomes. These findings suggest that this organelle is most likely similar to which of the following organelles? | back 33 chloroplasts |
front 34 A young child who suffers from a metabolic disease is always tired and fatigued. Which of the following organelles is most likely malfunctioning in this disease? | back 34 mitochondria |
front 35 Vinblastine, a drug that inhibits microtubule polymerization, is used to treat some forms of cancer. Cancer cells treated with vinblastine would most likely be unable to perform which of the following cellular functions? | back 35 separate chromosomes during cell division |
front 36 A phospholipid bilayer with equal amounts of saturated and unsaturated fatty acids displays a specific permeability to glucose. What effect will increasing the proportion of unsaturated fatty acids in the bilayer have on the membrane's permeability to glucose? | back 36 Permeability to glucose will increase. |
front 37 Cell membranes have distinct inside and outside faces. Which of the following statements is the most plausible explanation for the asymmetrical nature of the two layers of the membrane? | back 37 The two layers of a cell membrane face different environments and carry out different functions. |
front 38 A new drug designed for the treatment of lung cancer must specifically enter the cytoplasm of lung cells while not entering the cells of other tissues. Which of the following characteristics would likely enhance the specificity of this drug? | back 38 the similarity of the drug molecule to other molecules normally transported lung cells |
front 39 Which of the following statements best describes a characteristic feature of diffusion? | back 39 It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration. |
front 40 What will happen to a red blood cell (RBC), which has an internal ion content of about 0.9%, if it is placed into a beaker of pure water? | back 40 The cell will swell because the water in the beaker is hypotonic relative to the cytoplasm of the RBC. |
front 41 An organism with a cell wall would most likely be unable to take in materials through which of the following processes? | back 41 phagocytosis |
front 42 In what way do the membranes of a eukaryotic cell vary? | back 42 Certain proteins are unique to each membrane. |
front 43 According to the fluid mosaic model of membrane structure, proteins of the membrane are mostly | back 43 embedded in a lipid bilayer. |
front 44 Human immunodeficiency virus (HIV) infects cells that have both CD4 and CCRS cell surface molecules. The viral nucleic acid molecules are enclosed in a protein capsid, and the protein capsid is itself contained inside an envelope consisting of a lipid bilayer membrane and viral glycoproteins. One hypothesis for viral entry into cells is that binding of HIV membrane glycoproteins to CD4 and CCR5 initiates fusion of the HIV membrane with the plasma membrane, releasing the viral capsid into the cytoplasm. An alternative hypothesis is that HIV gains entry into the cell via receptor-mediated endocytosis, and membrane fusion occurs in the endocytotic vesicle. To test these alternative hypotheses for HIV entry, researchers labeled the lipids on the HIV membrane with a red fluorescent dye. What would be observed by live-cell fluorescence microscopy immediately after HIV entry if HIV enters the cell by endocytosis first, and then later fuses with the endocytic vesicle membrane? | back 44 The red fluorescent dye-labeled lipids will appear in the infected cell's interior. |
front 45 Which of the following processes includes all the others? | back 45 passive transport |
front 46 Which of the following factors, according to an evolutionary worldview, most likely helped early plants colonize land? | back 46 formation of mutualistic associations with fungi |
front 47 Which of the following statements correctly describes a characteristic of archegonia? | back 47 they may contain sporophyte embryos |
front 48 Assuming that they all belong to the same plant, which of the following lists the structures from largest to smallest? | back 48 gametophytes, antheridia, gametes |
front 49 Some fungal species live in plants and can kill herbivores that feed on the plant. What type of relationship does this fungus have with its host? | back 49 mutualistic |
front 50 In an investigation of Sphagnum growth, researchers measured the growth of four different S. Juscum species (labeled a, ab, bc, and c in the figure) at four temperatures. The results of the investigation are represented in the graph. | back 50 fuscum species are best adapted to live in warm climates. |
front 51 Researchers grew two plants of different species (plant 1 and plant 2) and added the same mycorrhizal species to the soil. They then measured the growth of each plant after one month. Plant 1 grew significantly more than plant 2. Which of the following conclusions is most consistent with these results? | back 51 plant 1 formed a mutualistic relationship with the mycorrhizal fungi and plant 2 did not |
front 52 Some companies advertise and sell mycorrhizae to home gardeners and commercial farms, claiming that the presence of mycorrhizae improves plant growth and survival. If the company conducted experiments on plants with and without mycorrhizae, which of the following results would support their claim? | back 52 increased production of corn ears in plants with mycorrhizae than in plants without mycorrhizae |
front 53 Name the organelle in a cell that secretes many MODIFIED proteins | back 53 Golgi Bodies |
front 54 Name the organelle in a cell recycles old or damaged organelles | back 54 Lysosomes |
front 55 Which is part of the endomembrane system? | back 55 All the above |
front 56 Name the organelle in a cell that converts solar energy to chemical energy | back 56 Chloroplast |
front 57 Which of the following conditions is required for a target organ to respond to a particular hormone? | back 57 The target organ must have receptors that recognize and bind the hormone molecule. |
front 58 When a neuron responds to a particular neurotransmitter by opening gated ion channels, the neurotransmitter is serving as a part of the signal pathway? | back 58 signal molecule |
front 59 Which of the following signal transduction proteins typically functions by forming dimers after binding to a signal molecule? | back 59 receptor tyrosine kinases |
front 60 Which of the following signal transduction proteins are activated by phosphorylation after binding to a signal molecule? | back 60 receptor tyrosine kinases |
front 61 Certain receptor tyrosine kinases (RTKs) that promote excessive cell division are found at high levels in various cancer cells. HER2 is an RTK that is present at excessively high levels in some breast cancer cells. Herceptin is a protein that binds to HER2 and inhibits cell division. Herceptin may be an effective treatment for breast cancer treatment under which of the following conditions? | back 61 If the patient's cancer cells have excessive levels of HER2. |
front 62 Which of the following activities would be inhibited by a drug that specifically blocks the addition of phosphate groups to proteins? | back 62 phosphorylation cascade |
front 63 A signal transmitted via phosphorylation of a series of proteins is generally associated with which of the following events? | back 63 conformational changes to each protein in the series |
front 64 How does the toxin of Vibrio cholerae cause profuse diarrhea? | back 64 It modifies a G protein involved in regulating salt and water secretion. |
front 65 Consider the following pathway:epinephrine -> G protein-coupled receptor -> G protein -› adenylyl cyclase - › CAMP Which of the following molecules serves as the second messenger in this pathway? | back 65 CAMP |
front 66 Which of the sequences below best describes the sequential steps (numbered 1-5) in a signal transduction pathway that utilizes a G protein-coupled receptor?
| back 66 3,1,5,2,4 |
front 67 Which of the following statements describes a characteristic feature of metaphase? | back 67 alignment of chromosomes on equator of the cell |
front 68 Which of the following statements best explains how neurons and some other specialized cells divide infrequently? | back 68 They have entered into G 0 . |
front 69 Cell A has half as much DNA as cells B, C, and D in a mitotically active tissue. Cell A is most likely in | back 69 G1 |
front 70 Which of the following is a molecule that helps to "turn off" the expression of genes in a cell? | back 70 corepressor |
front 71 When taken up by a cell, which of the following molecules binds to a repressor so that the repressor no longer binds to an operator? | back 71 inducer |
front 72 The unlettered circle at the top of the accompanying diagram shows a diploid nucleus with four unreplicated chromosomes. The circles labeled 1 to 5 show various combinations of these chromosomes. Which chromosomal configurations would be observed at prometaphase of mitosis? | back 72 II |
front 73 Which of the following conditions is most likely to result in transcription of the lac operon? | back 73 Which of the following conditions is most likely to result in transcription of the lac operon? |
front 74 Most cells that have become transformed into cancer cells have which of the following characteristics when compared to normal, healthy cells? | back 74 Shorter cell cycle |
front 75 Binding of a signaling molecule to which type of receptor leads directly to a change in the distribution of ions on opposite sides of the membrane? | back 75 ligand-gated ion channel |