15.1 Neurones and Nervous Coordination Flashcards
What are the two forms of coordination in animals
- The Nervous System 2. The Hormonal System
What does the nervous system use to coordinate responses
Nerve cells to pass electrical impulses along their length
What do electrical (nervous) impulses do
Stimulate their target cells by secreting neurotransmitters directly on them. This results in rapid and specific communication between specific parts of organisms
How long are nervous responses
Short lived
Where do nervous impulses occur
In localised regions
What does the hormonal system use to coordinate responses
Hormones which are transported in blood plasma to target cells
What do hormones do
Target cells have specific receptors on their cell-surface membranes and the change in hormone concentration stimulates them
How long are hormonal responses
They are long-lasting
Where do nervous impulses occur
Widespread
What are neurones
Specialised cells adapted to carrying nerve impulses from one part of the body to the other
What are the components of a mammalian motor neurone
- Cell body
- Dendrons
- An Axon
- Schwann cells
- Nodes of Raviner
- Myelin sheath
What is the cell body of a neurone
The cell body contains all usual organelles, but a large number of RER
This large number of RER is because of neurotransmitter and protein production
What are the dendrons of a neurone
Extensions of the cell body that further branch out into smaller fibres called dendrites, that carry nerve impulses TOWARDS the body
Where to dendrons/dendrites carry nerve impulses
TOWARDS the cell body
What is the axon of a neurone
A single long fibre that carries nerve impulses AWAY from the cell body
Hormonal system vs Nervous system
