Download Unit# 2B Practice Exam 2B_Cell_Exam_Review

Unit #2B: Cell Review Questions
2.3: Chemical Reactions & Enzymes
19. Why do most enzymes not function properly after being exposed to high temperatures?
a. they have been converted to tripeptides
b. their water content has been reduced
c. their bonding structure has been changed
d. they have combined with another enzyme
20. What determines the sequence and arrangement of amino acids in a protein?
a. the number of available atoms in an organism
b. the number of hydrogen atoms in fatty acids
c. the ratio of carbon, hydrogen, and oxygen atoms in carbohydrates
d. the information stored and translated by nucleic acids
21. Which of the following occurs during a biochemical reaction?
a. reactant atoms are destroyed and product atoms are formed
b. bonds of reactants are broken and atoms are rearranged into products
c. energy from the cell is converted into atoms of the products
d. atoms of the reactants are combined to form larger and more massive atoms of the products
22. Why are enzymes important to the 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
23. What is the name of the region at which reactants bind to an enzyme during a biochemical reaction?
a. catalyst
b. product
c. substrate
d. active site
24. How are enzymes able to speed up biochemical reactions?
a. they provide energy to the reactants
b. they absorb energy from the products
c. they lower the activation energy of the reaction
d. they increase the number of available reactant particles
2.4: Cell Energy (next page)
25. The energy available to the cell is stored in which part of the ATP molecule?
a. the phosphate tail
b. the nucleotide
c. the sugar
d. the ribose
26. ADP must combine with which of the following in order to regenerate ATP?
a. a free phosphate
b. a positive ion
c. an adenine base
d. a molecule of glucose
27. Which of the following is a produce of cellular respiration?
a. oxygen
b. carbon dioxide
c. glucose
d. sunlight
28. Glycolysis occurs in which part of the cell?
a. the thylakoid
b. the cytoplasm
c. the mitochondria
d. outside of the cell
29. What is the role of the Krebs cycle during aerobic respiration?
a. to produce oxygen
b. to avoid the buildup of lactic acid
c. to give up free phosphates for the recombination of ATP
d. to continue the breakdown of sugars in the mitochondria
30. What occurs during photosynthesis?
a. chemical energy is converted into light energy
b. light energy is converted into chemical energy
c. glucose is broken down to release energy
d. carbon dioxide and energy are released into the atmosphere
31. Which of the following are the essential raw materials for photosynthesis?
a. carbon dioxide and water
b. water and oxygen
c. glucose, water and carbon dioxide
d. glucose
32. Which of these terms describes the ability of an organism to maintain a relatively constant internal temperature?
a. osmosis
b. metabolism
c. homeostasis
d. passive transport