Lecture 3

Question 1

Metabolism

Answer 1

Metabolism

Question 2

Anabolism

Answer 2

• Synthesis of chemical compounds

- Energy is consumed (endergonic, meaning energy is consumed for this process)

Question 3

Catabolism

Answer 3

-
Breakdown of chemical compounds

• Energy is released (exergonic)

Question 4

Enzymes (function)

Answer 4

• Group of organic molecules (usually proteins) that bring about chemical changes while they themselves remain unchanged.
• Lower activation energy of reactions (days vs. seconds)
• Allow specific reactions to occur

Question 5

Most important enzyme in our body

Answer 5

Ribosome

Question 6

Induced fit model

Answer 6

Enzyme goes through conformational change to grasp substrate (so that it fits snug)

Question 7

apoenzyme

Answer 7

protein alone
(no substrate)

• ex: lysozyme

Question 8

holoenzyme

Answer 8

the functional enzyme that is protein + cofactor/coenzyme

Question 9

cofactor

Answer 9

inorganic component that assist in the enzyme’s functionality

• ex: taq polymerase needs magnesium (cofactor) to function

Question 10

Coenzyme

Answer 10

organic component that assists the enzymes functionality

• ex: NAD, and FAD

Question 11

Electron Carriers

Answer 11

Oxidized Reduced
NAD+ NADH

FAD FADH2

NADP+ NADPH

• move electrons from point A to point B

Question 12

Metabolic pathway

Answer 12

is a connected sequence of chemical reactions where product of one reaction is the substrate for the next reaction

• cells release or store energy via metabolic pathways

Question 13

Glycolysis (products)

Answer 13

• Net 2 ATP
• 2 Pyruvic acid
• 2 NADH

Question 14

Glycolysis (start with)

Answer 14

Glucose

Question 15

Energy investment phase (why)

Answer 15

• phosphorylating glucose provides activation energy (a bulky charged molecules makes the glucose molecule unstable)
• glucose diffuses into the cell via facilitated diffusion so attaching phosphate to it lowers the concentration of glucose in the cell (maintaining a concentration gradient)

Question 16

Substrate-level phosphorylation

Answer 16

• Transfer of Phosphate from one substrate to another

- how ATP is produced in glycolysis

Question 17

Aerobic Respiration (steps)

Answer 17

1. Synthesis of acetyl-CoA
2. Tri Carboxylic Acid Cycle (TCA)/Krebs Cycle
3. Electron transport chain

(oxygen is present)

Question 18

Anaerobic respiration

Answer 18

(oxygen is absent)

only bacteria can do this

Question 19

Synthesis of acetyl-CoA (products/reactants)

Answer 19

• 2 molecules of pyruvic acid in
• 2 molecules of NADH out
• 2 molecules of Acetyl-CoA out

Question 20

What gets oxidized in the Krebs cycle?

Answer 20

Acetyl CoA

Question 21

ETC

Answer 21

• Most significant production of ATP, using the Electron carriers

Question 22

ETC (location)

Answer 22

• Prokaryotes
• • in cytoplasmic membrane
• Eukaryotes
• • In cristae (mitochondria)

Question 23

ETC (4 molecules)

Answer 23

1. Flavoproteins
2. Ubiquinones
3. Metal-containing proteins
4. Cytochromes C

-

Question 24

Cytochrome complexes

Answer 24

• part of ETC

- use energy from electron carriers and pump H+ out of membrane to maintain concentration gradient

Question 25

Chemiosmosis

Answer 25

Mechanism for ATP formation is called chemiosmosis - protons flowing back into the cell via ATP synthase and in unisen produce ATP

Question 26

Oxidative phosphorylation

Answer 26

Chemiosmosis and ETC - production of ATP

Question 27

Kreb Cycle (products)

Answer 27

- 2 GTP --> 2 ATP - 6 NADH --> 16 ATP - 2 FADH2 --> 4 ATP - 4 CO2

Question 28

Anaerobic Respiration

Answer 28

- Producing ATP with molecules when oxygen is not present

Question 29

Anaerobic Respiration (other electron acceptors)

Answer 29

- Nitrate ion (NO3-) as final e- acceptor yields nitrite (NO2-) in E. coli - Sulfate (SO4=) as final e- acceptor yields H2S in Desulfovibrio - Carbonate (CO3=) as final e- acceptor yields methane in methanogens (Methanobacterium, Methanococcus) -

Question 30

Fermentation

Answer 30

- Uses own organic molecule as final electron acceptor in the absence of oxygen - is necessary to recycle NADH to NAD+ In the absence of oxygen (thus glycolysis can keep going without oxygen as long as NADH is recycled to NAD+

Question 31

Lactic Acid Fermentation

Answer 31

- Pyruvic acid is final electron acceptor - - NADH dumps its electron on to pyruvate and synthesizes lactate - Pyruvic acid converted to lactic acid

Question 32

Microorganism that can do Lactic Acid fermentation

Answer 32

Streptococcus lactis

Question 33

Alcoholic Fermentation

Answer 33

- Acetaldehyde is final electron acceptor | - Acetaldehyde converted to ethyl alcohol

Question 34

Microorganism that can do Alcohol fermentation

Answer 34

Saccharomyces cerevisiae

Question 35

When are proteins consumed

Answer 35

When fats and carbohydrates run out

Question 36

How proteins are broken down

Answer 36

- Protease catabolism protein into amino acids - the amino acids are then deaminated - the product is able to go into glycolysis or Krebs Cycle

Question 37

Lipase

Answer 37

Convert fats into fatty acids and glycerol

Question 38

Beta-oxidation

Answer 38

catabolism of fatty acids into 2 carbon units (which is converted into Acetyl CoA)