metabolism 2: fate of pyruvate

Question 1

NAD+

Answer 1

Glycolysis reduces NAD+ → NADH and H+

Question 2

NADH must be regenerated through

Answer 2

oxidative metabolism of pyruvate

Question 3

TCA cycle step 1

Answer 3

Pyruvate enters mitochondrial matrix
- H+ ions and pyruvate symport by facilitated diffusion

Question 4

TCA cycle step 2

Answer 4

pyruvate is converted by pyruvate dehydrogenase → acetyl-CoA

Question 5

look at rest of TCA cycle in notes

Question 6

where are all the enzymes in the TCA cycle located

Answer 6

in the matrix, apart from succinate dehydrogenase which is integrated into the inner mitochondrial membrane

Question 7

what are the products of the TCA cycle

Answer 7

ATP, NADH, CO2

Question 8

From each Acetyl-CoA, TCA cycle generates:

Answer 8

• ATP: 6-2 = 4
• NADH + H+ : 10
• FADH2: 2
• CO2: 6

Question 9

High ATP, NADH, acetyl-CoA =

Answer 9

lots of energy

Question 10

High ADP, NAD+ =

Answer 10

lack of energy

Question 11

High succinyl-CoA and acetyl-CoA =

Answer 11

lots of precursor molecules for biosynthetic reactions

Question 12

PDC deficiency (PDCD):

Answer 12

poor muscle tone, neurological disease in children, brain lesions, epilepsy, resp problems

Question 13

Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC):

Answer 13

defect in fumarate hydrate (before NADH generated), benign and malignant leiomyomas (skin tumours),