Unit 1

Question 1

What does type 1 diabetes mean

Answer 1

Failure to produce insulin

Question 2

What does type 2 diabetes mean

Answer 2

Loss of insulin receptor function

Question 3

What are microtubles

Answer 3

Hollow cylinders composed of tumbin

Question 4

Where do microtubles radiate from

Answer 4

MTOC microtuble organisational centre

Question 5

2 functions of the sodium potassium pump

Answer 5

1. Generate an ion concentration gradient
2. Glucose symport in the small intestine

Question 6

Role of ATP in a sodium potassium pump

Answer 6

To help with phosphorylation

Question 7

What is cytokinase

Answer 7

The separation of the cytoplasm of two daughter cells

Question 8

Degenerative diseases are….

Answer 8

When the normal control of the cell cycle leads to the expression of certain proteins associated with Alzheimer’s

Question 9

The response for increase in insulin

Answer 9

1. Binding of the peptide hormone insulin to the receptor which causes a conformational change which triggers phosphorylation of the receptor
2. The phosphorylation cascades inside the cell, leads to GLUT4 containing vesicles which are transported to the cell membrane of fat and muscle cells.
3. GLUT 4 is transported by proteins to allow glucose to pass across the plasma membrane and enter the cell.

Question 10

Target cells have….

Answer 10

Specific proteins to bind to therefore they have a specific binding sequences and responses.

Question 11

Resting membrane potential

Answer 11

State when there is no flow of ions across the membrane

Question 11

Action potential

Answer 11

Wave of electrical excitation along a neurons plasma membrane

Question 12

Describe the generation and transmission of a nerve impulse in neurons (7)

Answer 12

1.Resting membrane potential (give definition)
2.The transmitting of a nerve impulse requires changes in the membrane potential of the neurons plasma membrane
3. An action potential (give definition)
4. Neurotransmitters initiate a response by binding to their receptors at a synapse
5. Inactivation of the sodium channels and the opening of the potassium channels restores the resting membrane potential.
6. Depolarisation of a patch of membrane causes neighbouring regions of membrane to depolarise and go through the same cycle, as voltage gated sodium channels are opened.
7. When the action potential reaches the end of the neuron it causes vesicles containing neurotransmitters to fuse with the membrane and release the neurotransmitter which stimulates a response in a connecting cell.