Cell signalling

Question 1

Name 4 reasons why cells have to communicate?

Answer 1

PROCESS INFO-sensory stimul

SELF PRESERVATION-identify danger and take appropriate actions

VOLUNTARY MOVEMENT-brain communicates to different parts of the body

HOMEOSTASIS

Question 2

What kind of cell signalling is involved in homeostasis?

Answer 2

intercellular signalling

Question 3

What are the 4 types of intercellular signalling ?

Answer 3

• endocrine
• paracrine
• autocrine
• signalling by membrane attatched proteins

Question 4

What is endocrine signalling?

Answer 4

• hormones travel within blood vessels to act on distant cells
• intercellular signalling

e.g. in HYPOGLYCAEMIA glucagon produced in the pancreas acts on cells in the liver TO INCREASE BLOOD GLUCOSE

Question 5

Give examples of endocrine signalling?

Answer 5

Insulin-produced in liver and acts on pancreas

Adrenaline-produced in adrenal glands and acts on trachea to open airways =breath more easily

Question 6

What is paracrine signalling?

Answer 6

hormone acts on ADJACENT cell

Question 7

give examples of paracrine communication?

Answer 7

HYPERGLYCAEMIA- increased blood glucose =insulin secreted by beta cells in islets of langerhans and inhibits the secretion of glucagon

NITRIC OXIDE- produced from the endothelial cells in blood vessels to cause vasodialation=good if you have hypertension

OSTEOCLAST activating factors-produced by adjacent osteoblasts