20. Amoebae move by crawling over a surface (cell crawling), which involves _______.
(A) growth of actin filaments to form bulges in the plasma membrane
(B) assembly of microtubule extensions that vesicles can follow in the direction of movement
(C) reinforcement of the pseudopod with intermediate filaments
(D) localized contractions driven by myosin and microtubules

16. Cilia and flagella bend because of _______. (A) conformational changes in ATP that thrust microtubules laterally (B) a motor protein called radial spokes (C) contraction by myosin (D) a motor protein called dynein

17. Vinblastine, a drug that inhibits microtubule polymerization, is used to treat some forms of cancer. Cancer cells given vinblastine would be unable to _______. (A) form cleavage furrows during cell division (B) migrate by amoeboid movement (C) separate chromosomes during cell division (D) maintain the shape of the nucleus

18. Suppose a cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from _______. (A) a bacterium, but not a eukaryote (B) an animal, but not a plant (C) nearly any eukaryotic organism (D) a plant, but not an animal

19. Which cell would be best for studying lysosomes? (A) muscle cells (B) nerve cells (C) endocrine cells (D) phagocytic white blood cells

1. You are suffering from Streptococcus throat infection. You share the following with the bacteria that is responsible for your condition.(A)You both belong to the same domain.(B)You both are made up of cells.(C)You both have genetic material in your nucleus.(D) You and Streptococcus have nothing in common.

2. The evolution of one species into two or more species as a result of different populations becoming reproductively isolated from each other is best termed as_________. (A)adaptive radiation (B)creationism (C)natural selection (D) prototype

3. Cotton-topped tamarins are small primates with tufts of long white hair on their heads. While studying these creatures, you notice that males with longer hair get more opportunities to mate and father more offspring. To test the hypothesis that having longer hair is adaptive in these males, you should_________.(A)test whether other traits in these males are also adaptive(B)look for evidence of hair in ancestors of tamarins(C)determine if hair length is heritable(D) test whether males with shaved heads are still able to mate

4. Following a scientific method, which of the following is the correct order of steps?(A)Observation → Analysis → Hypothesis → Conclusion → Communicate results → Experiment(B)Observation → Hypothesis → Experiment → Communicate results → Analysis → Conclusion(C)Experiment → Hypothesis → Observation → Analysis → Conclusion → Communicate results(D) Observation → Hypothesis → Experiment → Analysis → Conclusion → Communicate results

5. Which of the following are compounds? (A)H2O, O2, and CH4 (B)H2O and O2 (C)O2 and CH4 (D) H2O and CH4, but not O2

6. Molybdenum has an atomic number of 42. Several common isotopes exist, with mass numbers from 92-100. Which of the following can be true? (A)Molybdenum atoms can have between 50 and 58 neutrons. (B)Molybdenum atoms can have between 50 and 58 protons. (C)Molybdenum atoms can have between 50 and 58 electrons. (D) Isotopes of molybdenum have different numbers of electrons.