chapter 5 learning objectives

Question 1

distinguish between metabolism, anabolism, and catabolism

Answer 1

metabolism: the sum of all chemical reactions, both anabolic and catabolic, within an organism.

catabolism: metabolism requires energy from the BREAK DOWN of acquired nutrients

anabolism: biosynthetic building up of larger building blocks

Question 2

contrast oxidation and reduction reaction

Question 3

compare and contrast 3 ways ATP can be produced

Answer 3

substrate level phosphorylation: phosphate added to ADP to create ATP in glycolysis and krebs cycle (citric acid)

oxidative phosphorylation: ETC, redox reaction, inorganic phosphate to ADP

photophosphorylation: light energy used to phosphorylate

Question 4

compare and contrast cellular respiration and fermentation

Question 5

discuss the 5 basic steps of metabolism and be able to describe what is happening in each step

Answer 5

1. entry of substrates- glucose enters the cell through facilitated diffusion or active transport
2. catabolism- transforms substrates into precursor metabolites (glucose 6-phosphate, fructose 6-phosphate, pyruvic acid), reducing power, and ATP
3. biosynthesis- construction of monomers
4. polymerization- monomers formed during biosynthesis joined together to form macromolecules (polymers) requires massive amounts of ATP
5. assembly- macromolecules into cellular structures

Question 6

distinguish between precursor metabolites, reducing power, and ATP, including why each is important for a cell

Answer 6

precursor metabolites are the product of catabolism which are then synthesized into a macromolecule.

reducing power is the reserve of hydrogen atoms stored in the reduced forms of NAD+, NADP+, or FAD. it is used to reduce metabolic intermediates and generate molecules of ATP

ATP (adenosine triphosphate) is a source of energy for the cell.

Question 7

describe the role of a proton gradient in oxidative phosphorylation

Answer 7

energy needed for ATP formation is provided by the proton gradient

Question 8

discuss the final electron acceptors in aerobic respiration, anaerobic respiration, and fermentation

Answer 8

aerobic respiration- final electron acceptor is oxygen

anaerobic respiration- final electron acceptor is an inorganic molecule other than oxygen (nitrate, sulfate)

fermentation- cellular organic molecules

Question 9

describe why an organism uses fermentation to break down carbohydrates

Answer 9

used by organisms that cannot completely oxidized glucose by cellular respiration. this means a suitable inorganic electron acceptor is unavailable or they lack an electron transport chain