Cellular Respiration

Question 1

what happens if we dont have o2 during cell respiration?

Answer 1

no final e acceptor in the etc –> etc will eventually shut down (aerobic respirtaion) –> NADH cannot be oxidized –> no NAD+ for glycolysis –> cell respiration SHUTS down

Question 2

what is the purpose of fermentation

Answer 2

keep glycolysis going without o2 by allowing e- to leave NADH to create NAD+ that will then oxidize G3P in glycolysis

Question 3

lactic acid fermentation

Answer 3

reduce PYRUVATE by taking e- from NADH
- creates LACTIC ACID and NAD+

Question 4

what does build up of lactic acid cause

Answer 4

• blood pH drops (co2 isn’t leaving (decarboxylation never occurs))
• ATP deficit: burning/cramping of overworked muscles
• Rigor mortis in dead tissue due to denaturation of proteins from lactic acid buildup

Question 5

where is lactic acid flushed out to

Answer 5

flushed out of muscle into blood where its converted into pyruvate in the liver (cori cycle)

Question 6

how is yogurt produced anaerobically

Answer 6

anaerobic bacteria produces lactic acid that denatures the protein in the milk after breaking the lactose down into glucose and galactose

Question 7

which creatures use lactic acid fermentation

Answer 7

humans and mammals

Question 8

why dont animals preform ethanol fermentation

Answer 8

they would get drunk

Question 9

how does yeast use anaerobic pathways

Answer 9

yeast removes the COOH from pyruvate cresting acetaldehyde and then oxidizes NADH producing ethenol
- COOH exits as CO2
- this is the bubbles in bread

Question 10

ethanol fermentation

Answer 10

• done by several species of bacteria/yeast
• PYRUVATE decarboxylates and becomes ACETYLADEHYDE
• reducing ACETYLADEHYDE results in ETHANOL and NAD+

Question 11

why do lipids have more energy than carbs

Answer 11

lipids have many fatty acids that break down into acetyl-coA (used in krebs)

Question 12

how do we get ATP from proteins

Answer 12

hydrolysis of peptide bond -> one a.a is cleaved off -> deamination (removing nh2) -> alpha-ketoacids produced –> enter krebs at various points depending on r-group

Question 13

What is glycolysis

Answer 13

turning 6C sugar into two 3C sugars
(glucose —> pyruvate)

Question 14

how many steps are in glycolysis

Answer 14

10, split into 2
steps 1-5: energy investment
steps 6-10: energy harvest

Question 15

where does glycolysis take place

Answer 15

cytosol in ALL cells

Question 16

what is step 1 of glycolysis

Answer 16

comitting glucose
- by attaching a PO4 from ATP, glucose is prevented from diffusing out

C6H11O6 + ATP —> G6P + ADP

Question 17

what does G6P stand for

Answer 17

Glucose-6-Phosphate

Question 18

step 2 glycolysis

Answer 18

G6P –> F6P
- isomers of each other
- aldose –> ketose
- if fructose directly consumed, step 1 is skipped and it enters glycolysis here

Question 19

what does F6P stand for

Answer 19

Fructose 6-phosphateq

Question 20

step 3 glycolysis

Answer 20

F6P + ATP –> F-1, 6- BP
- adding -PO4 to F6P

Question 21

F-1, 6-BP

Answer 21

Fructose-1,6-bisphosphate

Question 22

step 4 glycolysis

Answer 22

F-1, 6-BP –> G3P + DHAP
- 6C –> 3C + 3C
- DHAP cannot be used

Question 23

G3P

Answer 23

Glyceraldehyde 3-phosphate

Question 24

step 5 glycolysis

Answer 24

DHAP –> G3P
- isomers
- turning into something usable
- now we have TWO G3P, everything following will happen TWICE (products DOUBLE)

Question 25

summarize the events that occur in energy investment

Answer 25

- 2 ATP used - 1 ADP made - 2 G3P made

Question 26

step 6 glycolysis

Answer 26

G3P + PO4 + NAD+ --> 1,3 - BPG + NADH - oxidizing G3P, moving the electron to NAD+, becoming NADH - adding-PO4 to G3P

Question 27

1,3 - BPG stands for...

Answer 27

1,3-Bisphosphoglycerate

Question 28

step 7 glycolysis

Answer 28

1,3 - BPG + ADP --> 3 - PG - substrate level phosphorylation

Question 29

step 8/9 glycolysis

Answer 29

8. 3- PG --> 2-PG 9. 2-PG --> PEP - moving PO4 over - phosphorylation

Question 30

3-PG stands for....

Answer 30

3-Phosphoglyceric acid

Question 31

2-PG stands for..

Answer 31

2-Phosphoglyceric acid

Question 32

PEP stands for...

Answer 32

Phosphoenolpyruvate

Question 33

step 10 glycolysis

Answer 33

PEP + ADP --> ATP + Pyruvate

Question 34

what are the results of energy harvest

Answer 34

- 2 NADH made - 4 ATP made - 3 ADP used - 2 Pyruvate

Question 35

what are the results of GLYCOLYSIS

Answer 35

- NET gain of 2 ATP - net loss of 3 ADP - 2 Pyruvate made - 2 NADH made

Question 36

where does krebs cycle take place

Answer 36

matrix

Question 37

where is the matrix located

Answer 37

the space inside the inner membrane of the mitochondria

Question 38

Pyruvate Oxidation

Answer 38

- occurs from cytosol to matrix - pyruvate goes through decarboxylation (loses a CO2) - pyruvate oxidized = NAD+ reduced = NADH - CoEnzyme A added to pyruvate to lead into matrix - 3C --> 2C - becomes Acetyl-CoA

Question 39

step 1 krebs

Answer 39

Acetyl-CoA adds its 2C to OXALOACETATE (4C) creating CITRATE (6C)

Question 40

step 2 krebs

Answer 40

- ACONITATE made as a short-term intermediate as H2O shuffles around CITRATE (6C) --> ISOCITRATE (6C) thru the removal and addition of H2O

Question 41

step 3 krebs

Answer 41

oxidation and de-carboxylation - ISOCITRATE is oxidized =NAD+ reduced --> NADH - carboxyl group and exits as CO2 - 6C (ISOCITRATE ) --> 5C (ALPHA-KETOGLUTARATE)

Question 42

step 4 krebs

Answer 42

5C (ALPHA-KETOGLUTARATE) --> 4C (SUCCINYL-COA) - ALPHA-KETOGLUTARATE is decarboxylated, releasing CO2 - also oxidized = NAD+ reduced = NADH created - coA added again

Question 43

step 5 krebs

Answer 43

4C (SUCCINYL-COA) --> 4C (SUCCINATE) - CoA replaced by -PO4 - PO4 passed to GDP --> GTP --> ATP

Question 44

step 6 krebs

Answer 44

oxidation - SUCCINATE (4C) is OXIDIZED = FAD+ reduced = FADH2 created - 4C (SUCCINATE) --> 4C (FUMERATE)

Question 45

step 7 krebs

Answer 45

FUMERATE (4C) --> MALATE (4C) - water added

Question 46

step 8

Answer 46

oxidation - MALATE is oxidized = NAD+ reduced = NADH formed - MALATE becomes OXALOACETATE which can regenerate krebs cycle

Question 47

what would happen if oxaloacetate didnt regenerate in step 8?

Answer 47

- krebs cycle would eventually stop because you need oxaloacetate for acetyl-coA to attach to and begin the process - when krebs eventually stops, cell can no longer rely on aerobic respiration to make ATP and would have to go to anaerobic

Question 48

summarize the end results of krebs for each pyruvate

Answer 48

- 4 NADH made - 1 FADH2 made - 1 ATP - 3 CO2

Question 49

summarize the end results of krebs for each glucose

Answer 49

- 8 NADH made - 2 FADH2 made - 2 ATP - 6 CO2