Biological membranes - Cell Signalling

Question 1

what is cell signalling

Answer 1

communication between cells using chemicals, triggering a response inside cells

Question 2

describe the process of cell signalling

Answer 2

• cell signalling molecules are chemicals released by a cell that have specific shapes
• they bind to receptors (e.g glycoprotein) on the cell surface membrane of target cells
• receptor and cell signalling molecules have complementary shapes
• binding stimulates a reaction inside the cell

Question 3

what does ATP become when catalysed by adenylyl cyclase

Answer 3

cyclic AMP + 2Pi

Question 4

explain the two examples of hormones binding to specific receptors triggering a response in the cell

Answer 4

glucagon - binds to receptors on liver cells causing glycogen to be broken down to glucose
FSH - binds to receptors in ovaries, causing an egg to mature ready for ovulation

Question 5

explain the two examples of drugs working by binding to receptors either triggering a response or blocking the receptor

Answer 5

morphine - binds to opioid receptors in the brain to reduce transmission of pain signals
antihistamines - block receptors on cell surfaces preventing histamine binding which would otherwise cause inflammation