1.7

Question 1

the role of ATP in energy transfer

Answer 1

ATP is used to transfer energy to synthetic pathways and other cellular processes where energy is required

Question 2

phosphorylation

Answer 2

is an enzyme controlled process by which a phosphate group is added to a molecule

Question 3

Cellular Respiration is a process by which energy is made for processes such as

Answer 3

Muscle cell contraction
Protein synthesis
Active Transport
DNA replication

Question 4

There are 3 stages involved in respiration:

Answer 4

1. Glycolysis – Occurs in the cytoplasm
2. Citric Acid Cycle – Occurs in the matrix of the mitochondria
3. Electron Transport Chain – Occurs In the inner membrane of the mitochondria

Question 5

Stage 1 – Glycolysis

Answer 5

Glycolysis is the breakdown of glucose into 2 pyruvate molecules. It occurs in the cytoplasm and no oxygen is required for this process

The production of pyruvate from glucose involves the production of several intermediate compounds

During glycolysis dehydrogenase enzymes remove hydrogen ions and electrons. The hydrogen carrier (coenzyme) NAD picks up hydrogen ions released during the reaction forming NADH and carries them to stage 3.

Question 6

stage 2 - citric acid cycle

Answer 6

This stage occurs in the matrix of the mitochondria and only occurs in aerobic conditions

Here pyruvate is converted to an acetyl group - Acetyl combines with Coenzyme A to form Acetyl coenzyme A.

Acetyl CoA combines with a molecule called oxaloacetate to form citrate.

As in glycolysis, dehydrogenase enzymes remove hydrogen ions and electrons. The hydrogen carrier (coenzyme) NAD picks up hydrogen ions released during the reaction forming NADH and carries them to stage 3.

Question 7

Stage 3 – Electron Transport Chain

Answer 7

The Final stage occurs in the inner membrane of the mitochondria and yields the highest amount of ATP.

NADH release the hydrogen ions and electrons collected previously into the transport chain.

The electrons transfer their energy to the proteins in the membrane. This provides energy for the hydrogen ions to be pumped across the inner mitochondrial membrane.

The flow of ions back across the membrane synthesises ATP by a protein called ATP synthase. (34 ATP molecules)

, oxygen is the final hydrogen ion and electron acceptor. The oxygen combines with the hydrogen ions and electrons to form water.

Question 8

function of dehydrogenase enzymes

Answer 8

removes hydrogen ions and electrons from substrates