Hormonal Homeostatic (PPT 4) [U2/ T1] Flashcards
1
Q
What are hormones?
A
- Hormones are chemical messengers
- Highly effective in small concentrations
- Target specific cells that carry specific receptors for specific hormones.
- Function is to regulate cell function
- Produced generally by endocrine glands which release these messengers into either the bloodstream or lymphatic system.
- Endocrine glands secrete products directly into the bloodstream
- Exocrine glands secrete their products via a duvet
2
Q
How do hormones talk to cells (signal transduction)
A
- Signal transduction is converting one signal into a different format just like in a stimulus-response model.
Its a 3 step process
1) Reception
2) Transduction
3) Cellular Response
3
Q
What does reception include?
Signal transduction
A
- Detection of the signalling molecule
- Receptors can be located on the membrane or inside the cell
- The position of the receptor depends on whether the hormone can cross the membrane or not
- Receptors are located either on the cell membrane, or inside the target cell
- Their position depends on the chemical composition of the hormone and its membrane solubility.
4
Q
What does signal transduction include?
A
- Convert the signal into a format the cell can read
- Can be simple translation or multi stepped
- Either way there is often messengers involved
5
Q
What does cellular response include?
A
- The initiation of a cellular response
- The response varies depending on the hormone
6
Q
Name the signaling molecule
Synapse
A
Neurotransmitter
7
Q
Where is the receptor located (post or presynaptic terminal?)
(Synapse)
A
Post synaptic terminal
8
Q
Describe the cellular response initiated from the signalling molecules binding to the receptor
(Synapse)
A
The neurotransmitters binding to receptors causing channels to open which begins the action potention
9
Q
How are the nervous and endocrine systems linked
A
- The systems are linked at the hypothalamus
