Lecture two, cell metablism glycolysis and citric acid cycle

Question 1

Name the 8 intermediates and enzymes in the citric acid cycle

Answer 1

8 intermediates: citrate, iso-citrate, alpha-ketoglutarate, succinate, fumarate, malate, and oxaloacetate
8 enzymes: Citrate synthase, Aconitase, Isocitrate dehydrogenase, α-ketoglutarate dehydrogenase, Succinyl-CoA synthetase, Succinate dehydrogenase, Fumarase, Malate dehydrogenase

Question 2

What is the net worth fo energy from glycolysis and citric acid cycle?

Answer 2

For glycolysis: 2 ATP and 2 NADH

For citric acid cycle: 3NADH, 1FADH2 1GTP.

Question 3

· Describe the basic functions of glycolysis and the citric acid cycle

Answer 3

The function of glycolysis it to turn glucose into pyruvate that can enter the citric acid, generate ATP and NADH and provide the cell with energy under anaerobic circumstances. The citric acid cycle function is to make and GTP and NADH and FADH2 that then can enter the electron carrying chain.

Question 4

· Describe where and under what conditions these pathways work

Answer 4

Glycolysis occurs in the cytoplasm and does not require oxygen so it’s an anaerobic reaction. The citric acid cycle requires oxygen so it’s an aerobic reaction and it occurs in the matrix of the mitochondria.

Question 5

Name the key steps in glycolysis

Answer 5

Glycolysis starts with one glucose molecule and 2 ATP as an energy investmeant. There are three irreversible steps in glycolysis, when glucose transforms inte glucose-6-phostphate, fructose-6-phostphate transforms into fructose-1,6-biphostphate and PEP turns into pyruvate.