Sponge #1 8-13-12

1. Sponge #1 8-13-12 If scientists search other planets for possible life, they are likely to focus on the presence of molecules containing which of the following elements? A. carbon B. iron C. potassium D. sodium

2. Answer: A. carbon

3. Sponge #2 8-14-12 An organism’s genetic information is stored in which type of macromolecule? A. Protein B. Carbohydrate C. Lipid D. DNA

4. Answer: D. DNA

5. Sponge #3 8-15-12 When the sugar lactose is digested by the human body, each lactose molecule is broken down into smaller molecules. To which of the following categories do these smaller molecules belong? A. amino acids B. monosaccharides C. nucleic acids D. polypeptides

6. Answer: B. monosaccharides

7. Sponge #4 8-16-12 Many plants have waxy coatings on some surfaces. This coating reduces water loss because it is not water-permeable. This waxy coating is which of the following types of organic molecule? A. Carbohydrate B. Lipid C. Nucleic acid D. Protein

8. Answer: B. Lipid

9. Sponge #5 8-17-12 Ovalbumin is a protein found in eggs. Which of the following best describes the molecular structure of ovalbumin? A. A group of six carbon atoms joined in a ring B. A set of three fatty acids attached to a molecule of glycerol C. A chain of amino acids folded and twisted into a molecule D. A sequence of nitrogenous bases attached to a sugar-phosphate backbone

10. Answer: C. A chain of amino acids folded and twisted into a molecule

11. Sponge #6 8-20-12 Enzymes affect the reactions in living cells by changing the A. Products of the reaction. B. Speed of the reaction. C. Temperature of the reaction. D. pH of the reaction.

12. Answer: B. Speed of the reaction.

13. Sponge #7 8-21-12 Enzymes only work with specific substrates because each enzyme: A. Has a specific activation site for substrate attachment B. Can only use a specific ionic bond with the substrate C. Destroys its substrate D. Actively interferes with other substrates around it

14. Answer: A. Has a specific activation site for substrate attachment

15. This graph shows that: A. More enzymes are present at a higher pH B. Pepsin is less sensitive to pH that trypsin C Pepsin is less effective at low pH than trypsin D. pH affects the activity rate of enzymes Sponge #8 8-22-12

16. Answer: D. pH affects the activity rate of enzymes

17. Students in a biology laboratory are monitoring the rate at which hydrogen peroxide breaks down to produce water and oxygen gas. They begin monitoring a sample of hydrogen peroxide and then add catalase, an enzyme that speeds up its breakdown. Their data are shown in the table below. Based on the data in this table, during which of the following time periods did the students add the catalase to the hydrogen peroxide? A. Between 0.0 and 0.5 B. Between 1.0 and 1.5 C. Between 2.0 and 2.5 D. Between 2.5 and 3.0 Sponge #9 8-23-12

18. Answer: B. Between 1.0 and 1.5

19. Sponge #10 8-24-12 How are enzymes important in the proper functioning of the human body? A. They keep the pH of the body within acceptable levels. B. They help essential biochemical reactions occur fast enough to maintain homeostasis. C. They enable the body to use energy to produce food. D. They provide cells with energy they need to carry out life functions.

20. Answer: B. They help essential biochemical reactions occur fast enough to maintain homeostasis.

21. Sponge #11 8-27-12 Which pair of structures best shows that plant cells have functions different from animal cells? • Cytoplasm and mitochondria • Chloroplasts and cell walls • Nuclei and centrioles • Ribosomes and cell membranes

22. Answer: B. Chloroplasts and cell walls

23. Sponge #12 8-28-12 Which of the following is NOT a principle of the cell theory? • Cells are the basic unit of life • All living things are made of cells • Very few cells reproduce • All cells are produced by existing cells

24. Answer: C. Very few cells reproduce

25. Sponge #13 8-29-12 Unlike prokaryotic cells, eukaryotic cells have the capacity toA. assemble into multicellular organisms B. establish symbiotic relationships with other organisms C. obtain energy from the Sun D. store genetic information in the form of DNA

26. Answer: A. assemble into multicellular organisms

27. Sponge #14 8-30-12 Which of the following is a function of the nucleus? • Stores DNA • Controls most of the cell’s processes • Contains the information needed to make proteins • All of the above

28. Answer: D. All of the above

29. Sponge #15 8-31-12 A type of cell that can exist in a broad range of environmental conditions, can rapidly multiply, and lacks a nucleus is known as what type of cell? A. animal B. eukaryotic C. plant D. prokaryotic

30. Answer: D. prokaryotic

31. Sponge #16 9-4-12 Which cell organelle is most directly involved with the bonding of amino acids? A mitochondrion B endoplasmic reticulum C cell wall D ribosome

32. Answer: D ribosome

33. Sponge #17 9-5-12 Which organelle contains digestive enzymes and breaks down food into molecules the cell can use? • Nucleolus • Lysosome • Chromatin • Cell wall

34. Answer: B. Lysosome

35. Sponge #18 9-6-12 Some cells, such as human nerve and muscle cells, contain many more mitochondria than do other cells, such as skin cells. Why do some cells have more mitochondria than others? • The cells use more energy • The cells store more nutrients • The cells degrade more proteins • The cells divide more frequently

36. Answer: A. The cells use more energy

37. Sponge #19 9-7-12 Which of the following is a function of the cell membrane? • Breaks down lipids, carbohydrates, and proteins from foods • Store water, salt, proteins, and carbohydrates • Keeps cell wall in place • Regulates which materials enter and leave the cell

38. Answer: D. Regulates which materials enter and leave the cell

39. Sponge #20 9-10-12 Passive transport differs from active transport in that passive transport: • Uses ATP from the cell’s mitochondria • Requires twice as much energy to take place • Uses energy form the cell’s energy reserves • Does not require energy from ATP to take place

40. Answer: D. Does not require energy from ATP to take place

41. Sponge #21 9-11-12 Osmosis is an example of A. cytolysis. B. active transport. C. passive transport. D. a chemical change.

42. Answer: C. passive transport.

43. Sponge #22 9-12-12 Cells use passive and active transport to move materials across cell membranes in order to maintain a constant internal environment. What is the process of maintaining a constant internal environment called?A. diffusion B. evolution C. homeostasis D. respiration

44. Answer: C. homeostasis

45. Sponge #23 9-13-12 A red blood cell is placed in a 0.9% salt solution. If there is a 0.1% salt solution inside the cell, then the salt solution the cell was placed in is: A. isotonic. B. hypotonic. C. hypertonic. D. hydrostatic.

46. Answer: C. hypertonic.

47. Sponge #24 9-14-12 A plant cell is placed in hypotonic solution. What will happen to the plant cell? • It will swell. • It will shrink. • It will stay the same. • It will wilt.

48. Answer: • It will swell.

49. Sponge #25 9-17-12

50. Answer: D. a virus