Section 5

Question 1

What are co enzymes?

Answer 1

A molecule that helps the function of an enzyme
They work by transfering a chemical group from one molecule to another

Question 2

Describe the process of glycolysis

Answer 2

Occurs in the cytoplasm
Glucose is phosphorylated by adding two phosophate groups and glucose phospahte is made
The phosphate comes from 2 ATP
This is split into two triose phosphate
Triose phosphate is oxidised as protons and electrons are removed from it
These electrons are accepted by NAD to form reduced NADH this forms pyruvate
The phosphates are removed and energy is released to make ATP by substrate level phosphorylation

Question 3

What are the products of glycolysis?

Answer 3

2 reduced NADP
2 ATP

Question 4

What is substrate level phosphorylation?

Answer 4

When ADP in converted into ATP by the direct transfere of a phosphate group from a phosphorylated intermediet

Question 5

What is oxidative phosphorylation or photophosphorylation?

Answer 5

when a chemiosmotic gradient (protons) is used to power the phosphorylation process
The phosphate comes from a pool of inorganic phosphate in the matrix/ stroma

Question 6

What is chemiosmosis?

Answer 6

the process where movement of protons across a biological membrane generates ATP

Question 7

Lable the structre of a mitochondria

Answer 7

Question 8

What happens in the link reaction?

Answer 8

Pyruvate enters the matrix by active transport - only if oxygen is avalible
It is oxidised - protons and electrons are removed and picked up by NAD–> NADH is produced
Pyruvate is decarboxylated - CO2 is removed, acetate combines with co enzyme A to make acetyl coA

Question 9

What happens in the kerbs cycle?

Answer 9

Acetyl coAenters and CoA is released
acetyl combines with a 4C to make a 6C
2CO2 is released
3NAD are reduced to 3NADH
FAD reduced to FADH2
ATP is formed

Question 10

What happens in the electron transport chain?

Answer 10

1) electrons come from reduced NAD and FAD
2) electrons are passed between carriers in a series of redox reactions and they loose energy
3) protons are actively transported using energy from the electrons through the membrane from the matrix to the intermembrane space
4) protons accumulate in the space so thee is a gradient fored
5) protons travel back down their concentration gradient back into the matrix via ATP synthase (chemiosmosis)
6) ATP synthase makes ATP by oxidative phosphorylation
7) electrons from the end of the ETC are picked up by oxygen along with protons and water is made
8) oxygen is the final electron acceptor