Signalling between cells I

Question 1

Why must cells communicate?

Answer 1

Info processing

Self preservation

Voluntary movement

Homeostasis

Question 2

What are two methods of communication?

Answer 2

Nervous
- electrical

Endocrine
- hormonal - chemical

Question 3

What occurs in glucose homeostasis?

Answer 3

Hyperglycaemia

• glycogen formed
• reduction of below by paracrine effects of insulin on glucagon via alpha cells

Hypoglycaemia

• glycogenolysis
• gluconeogenesis

Question 4

How might cells signal to eachother

Answer 4

Membrane attached proteins

• APCs to TCR - MHC
• HIV GP120 to CD4

Question 5

Give an ecample of autocrine signalling

Answer 5

Activated TCR inititates cascade

• IL-2 receptor present
• IL-2 secreted, binds to receptor

ACh on presynaptic receptors