Chapter 5: Essential Concepts Of Metabolism

Question 1

Anabolism

Answer 1

Use energy to build bigger molecules from smaller molecules

- amino acids to proteins

Question 2

Catabolism

Answer 2

Taking a larger molecule and breaking it down to its basic components, releasing energy to be used by the cell
- protein to amino acids

Question 3

ATP

Answer 3

Adenosine triphosphate

- cells main source of energy

Question 4

Oxidation

Answer 4

Loss of electrons

• loss of energy (exothermic)
• loss of hydrogen, gain an oxygen

Question 5

Reduction

Answer 5

Gain of electrons

• gain hydrogen and energy (endothermic)
• loss of oxygen

Question 6

Autotrophs

Answer 6

Make their own food

- use CO2 as their carbon source

Question 7

Photoautotrophs

Answer 7

Use light as their energy source

Question 8

Chemoautotrophs

Answer 8

Use inorganic compounds (iron, sulfur) as their energy source

Question 9

Heterotrophs

Answer 9

Don’t make their own food, use organic compounds as carbon source

Question 10

Photo heterotrophs

Answer 10

Purple and green non sulfur bacteria

- somewhat rare

Question 11

Chemoheterotrophs

Answer 11

Organic compounds are energy and carbon source

- all protozoans, fungi, animals

Question 12

Metabolic pathway

Answer 12

Uses enzymes to turn molecules into other molecules

Question 13

Enzymes

Answer 13

Proteins that are catalysts (speed up the rate of reaction without being used or changed)

• work by lowering activation energy
• substrates bind to active site and transform

Question 14

Apoenzyme

Answer 14

Protein portion of enzyme (enough for some enzymes)

Question 15

Coenzyme

Answer 15

Nonprotein, organic molecule that carries electrons (derived from vitamins)

• NADH/NAD+
• FAD/FADH2

Question 16

Cofactor

Answer 16

Inorganic molecule that helps improve the fit to the active site
- Zn, Mg ions

Question 17

Holoenzyme

Answer 17

Complete, functional enzyme

• some apoenzymes are holoenzymes
• could be apoenzyme+cofactor+coenzyme

Question 18

Competitive inhibition

Answer 18

Molecule (competitive inhibitor) is competing with a substrate for the active site on an enzyme
- sulfa drugs (inhibit PABA from binding to enzyme to be converted into folic acid (needed for bacteria))

Question 19

Non competitive inhibition

Answer 19

Molecule binds to another site (allosteric site) and distorts the active site so substrates can’t bind
- irreversible, ex. Poisons like mercury inhibit enzymes

Question 20

Influences on reaction rate

Answer 20

• Temperature: ^ leads to ^ enzyme activity up to optimum temperature
• pH: optimum ~7
• substrate: ^ substrate, ^ rate
• product: ^ product, v rate
• enzyme: ^ enzyme, ^ rate

Question 21

Fermentation

Answer 21

Anaerobic process that reoxidizes NADH to allow NAH+ to be used in glycolysis

• doesn’t produce ATP
• substrate: pyruvate
• multiple pathways (propionic, butyric-butylic, butanediol)

Question 22

Homolactic pathway

Answer 22

Produces lactic acid

Question 23

Alcoholic pathway

Answer 23

Produces ethyl alcohol

Question 24

Aerobic respiration

Answer 24

Glycolysis + krebs + ETC

- allows extraction of energy from high energy electron carriers to make ATP