TOPIC 4: TCA CYCLE

Question 1

TCA in fed state occurs at

Answer 1

Question 2

Where do glycolysis and TCA cycle occur

Answer 2

Glycolysis
- Eukaryotes and prokaryotes = cytoplasm
TCA Cycle
- Eukaryotes – mitochondrial matrix
- Bacteria – cytoplasm

Question 3

TCA overview

Answer 3

Question 4

Mitochondrial transport systems

Answer 4

• Transporters for many key metabolites
• Pyruvate transporter/ carrier transports pyruvate in for H +
• Pyruvate- (i.e. it is negatively charged)
• Secondary active transporter

Question 5

primary transport

Answer 5

energy used to drive solute movement against concentration gradient

Question 6

Secondary transport

Answer 6

a gradient already established by primary active transport is used to cotransport a second solute

Question 7

Production of acetyl CoA

Answer 7

• Once pyruvate is inside the mitochondria, it can start to be metabolised
• The first step is conversion to acetyl CoA:
• This is an oxidative decarboxylation reaction
• Irreversible

Question 8

• Pyruvate dehydrogenase is a complex consisting of three distinct enzymes
• It also requires 5 coenzymes, what are these?

Answer 8

1. Thiamine pyrophosphate (TPP)
2. Flavin adenine dinucleotide (FAD)
3. Lipoate
4. Nicotinamide adenine dinucleotide (NAD)
5. Coenzyme A (CoASH)

Question 9

The acetyl CoA formed is a

Answer 9

Thiol ester

Question 10

Beer-Lambert Law

Answer 10

• This law relates the amount of light absorbed (or transmitted) through a substance to the properties of that particular substance

Question 11

Beers Law

Answer 11

amount of light absorbed is directly proportional to the concentration of a solution (c)

Question 12

Lamberts Law

Answer 12

amount of light absorbed is directly proportional to the path length (l)