Unit 1 Section 2: Cell membranes and signalling Flashcards Preview

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Flashcards in Unit 1 Section 2: Cell membranes and signalling Deck (8)
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1
Q

importance of cell signalling

A

cells need communicate to control processes inside the body and respond to changes in the environment

2
Q

cell signalling starts…

A

when one cell releases a messenger molecule such as a hormone. this travels to another cell, where it is detected because it binds to a receptor on the cell membrane. this triggers a change in the cell, e.g. chemical signals sent off.

3
Q

membrane bound proteins…

A

act as receptors for messenger molecules

4
Q

receptor proteins

A

have specific shapes so that only messenger molecules with a complementary shape can bind to them. different cells have different types of receptor, meaning they respond to different messenger molecules. when a cell responds to a particular molecule it is called the TARGET CELL. cells can have many combinations of receptor cells they are not restricted to 1.

5
Q

examples of hormone messenger molecules

A
  • Glucagon is a hormone released when there isn’t enoughglucose in the blood. It binds to receptors on liver cells causing liver cells to break down stores of glycogen to glucose.
  • FSH hormone is released by the pituitary gland during the menstrual cycle. It binds wuth receptors on cells in the ovaries, causing an egg to mature, ready for ovulation.
  • FSH can also bind to cells in the testes to initiate the production of sperm.
6
Q

role of drugs

A

some drugs also bind to receptors in cell membranes. they either trigger a response or block a receptor preventing it from working.

7
Q

drug examples

A
  • Morphine binds to the same recepters an endorphins and triggers a reduction in pain signals that are sent.
  • Antihistamines block histamine receptors on the surface of cells preventing histamine from binding, therefore reducing inflammation.
8
Q

define antagonistic molecules

A

a molecule that blocks the action of another.