| How do cells communicate with one another | by cell signaling, which uses messenger molecules |
| How are messenger molecules used in cell signalling | 1) One cell releases a messenger molecule ( e.g. a hormone)
2) This molecule travels (e.g. in the blood) to another cell - the target cell
3) The messenger molecule is detected by the cell because its binds to a receptor on its plasma membrane |
| What are receptors | proteins that have a specific shape, meaning only a messenger molecule with a complimentary shape can bind to them |
| How do hormones act as messenger molecules | They work by binding to receptors in cell membranes and triggering a response in the cell. |
| Give 2 examples hormones used in cell signalling | glucagon - when there isn't enough glucose in the blood, it is broken down to release glucose
FSH - released by pituitary gland during menstrual cycle |
| How do drugs work on receptors, give examples | They either trigger a response in the cell, or block the receptor and prevent it from working. |
| What do antihistamines do | - cell damages causes the release of histamine.
- Histamine binds to a receptor on the surface of other cells and causes inflammation.
- Antihistamines work by blocking histamine receptors on the cell surfaces, preventing histamine from binding to the cell and stops inflammation. |
| How does morphine work | - the body produces chemicals called endorphins, to relieve pain
- endorphins bind to opioid receptors in the brain to reduce the transmission of pain signals
- morphine is a drug used to relieve pain by binding to the same opioid receptors as endorphins also triggering a reduction in pain signals |
