Chapter 5 pre-test
Which of the following is true of catabolism?
Catabolic reactions are exergonic; they break down complex organic molecules into simpler ones.
Which of the following statements is true about enzymes?
Each enzyme has a characteristic three-dimensional shape.
The chemical reactions involved in synthesizing proteins & cell wall peptidoglycan are examples of ______ reactions.
anabolic
Which of the following statements is accurate concerning glucose metabolism?
Pyruvic acid, the product of glycolysis, is the starting block for both Krebs cycle and fermentation.
The complete oxidation (catabolism) of glucose typically involves three stages. The greatest amount of ATP is produced in which stage?
The electron transport chain.
Which of the following molecules carry electrons during various stages of glucose catabolism?
NADH & FADH2
Which of the following four stages of glucose oxidation requires molecular oxygen?
Oxidative phosphorylation.
Which of the following statements accurately describes the difference between aerobic & anaerobic respiration?
Aerobic respiration uses oxygen as the final electron acceptor & anaerobic respiration uses either an inorganic molecule, such as nitrate ions or sulfate ions, or an organic molecule, such as an acid or alcohol.
Carbon fixation occurs during ______________.
photosynthesis
Fermentation differs from anaerobic respiration in all of the following ways EXCEPT that fermentation does NOT _________.
use an electron transport chain
When fermentation test are used to help identify bacteria, which of the following end-products is typically detected by a color or change?
Acid
Which of the following are products of light-dependaent(in italics) photosynthetic reactions & are necessary for the light-independent(in italics) photosynthetic reactions occur?
ATP & NADPH
During the light-independent reactions of photosynthesis, organisms _____.
synthesize sugars
Nitrobacter(italics) bacteria use carbon dioxide for their carbon source & nitrate ions as an energy source. This organism is a _____.
chemoautotroph
Which group of organisms has members representing each of the following nutritional classifications: chemoheterotrophs, chemoautogrophs, photoheterotrophs, & photoautotrophs?
Bacteria
Which of the following molecules traps energy released during oxidation reduction reactions?
ATP
Some amino acids are synthesized by adding an amine group to pyruvic acid or to one of the Krebs cycle intermediates. This process is known as ______.
Amination
You inoculate a bacterial culture into a tube containing glucose & peptides. The pH indicator shows that the pH decreased after 24 hours & then increased at 48 hours. What has caused the increase in pH?
Deamination
Which of the following terms refers to pathways that can function both in anabolism & catabolism?
Amphibolic pathways
Like glucose, amono acids are catabolized for energy, but these must be converted to a form where they can enter the Krebs cycle for oxidation. All of the following reactions occur in the catabolism of amino acids EXCEPT __________.
carbon fixation