12. Tay-Sachs disease is a human genetic abnormality that results in cells accumulating and becoming clogged with very large, complex, undigested lipids. Which cellular organelle is most likely defective in this condition?
(A)the lysosome
(B)the Golgi apparatus
(C)the smooth endoplasmic reticulum
(D) the rough endoplasmic reticulum

8. Rank, from low to high, the pH of blood, stomach acid, and urine.(A)blood, urine, and stomach acid(B)stomach acid, blood, and urine(C)urine, blood, stomach acid(D) stomach acid, urine, blood

9. How would acidification of seawater affect marine organisms? Acidification of seawater would (A)increase dissolved carbonate concentrations and promote faster growth of corals and shell-building animals (B)decrease dissolved carbonate concentrations and promote faster growth of corals and shell-building animals (C)increase dissolved carbonate concentrations and hinder growth of corals and shell-building animals (D) decrease dissolved carbonate concentrations and hinder growth of corals and shell-building animals

10. Which of the following statements correctly describes cis-trans isomers?(A)They have variations in arrangement around a double bond.(B)They have an asymmetric carbon that makes them mirror images.(C)They have the same chemical properties.(D) They have different molecular formulas.

11. What is the explanation for how a modern transmission electron microscope (TEM) can achieve a resolution of about 0.2 nanometers, whereas a standard light microscope has a maximum resolution of about 200 nanometers? (A)Glass lenses in light microscopes refract light, which reduces resolution. (B)Contrast is enhanced by staining with atoms of heavy metal. (C)Electron beams have much shorter wavelengths than visible light. (D) The electron microscope has a much greater ratio of image size to real size.

13. If plant cells are grown on media containing radioactively labeled thymine for one generation, radioactively labeled macromolecules will be detected in which of the following? (A)only in the nucleus (B)only in the nucleus and mitochondria (C)only in the nucleus and chloroplasts (D) in the nucleus, mitochondria, and chloroplasts

14. Most cells cannot harness heat to perform work because_________.(A)heat is not a form of energy(B)temperature is usually uniform throughout a cell(C)heat can never be used to do work(D) heat must remain constant during work

15. Research on conditions that are relatively new to human populations such as myopia, breast cancer, and obesity support the conclusion that_________. (A)human populations have accumulated a number of mutations that have become fixed by genetic drift (B)the changes in human lifestyle account for all of the increase in frequencies of these conditions (C)these conditions are indeed "diseases of civilization" and are likely caused by the interaction between genes (genetic susceptibility) and novel environments (D) these human conditions are mere artifacts of the way in which they have been evaluated

1. What is the average net torque on the wheel during this time interval?(A) (B)(C) (D)(E)

2. What is the average power input to the wheel during this time interval?(A) (B) (C) (D)(E)

3. What is the ratio of (A) 2½ (B) (C) (D) (E)