Topic 39 - Nervous tissue : Synapses

Question 1

Where does synapses exist?

Answer 1

between neurons, where on neuron influences another.

Question 2

What types are there?

Answer 2

• Electrical: gap junctions (paired hydrophilic pore channels) between membranes of adjacent neurons.
• Chemical: change in membrane potential of post-synaptic neuron by release of neurotransmitters from the pre-synaptic neuron.

Question 3

Types - based on depolarization

Answer 3

• Isotropic – linked to ion channels for depolarization.

- Metabotropic – linked to metabolism for depolarization.

Question 4

Types – based on post-synaptic site

Answer 4

• Axodendritic
• Axospinous
• Axosomatic

Question 5

Types – based on function

Answer 5

• Excitatory: asymmetrical membrane thickness. Rounded vesciles.
• Inhibitory: symmetric

Question 6

Neurotransmitters:

Answer 6

• Acetylcholine.
• Amino acids – glutamate, aspartate.
• Amino acid derivatives – serotonin, dopamine.
• Peptides – opiods (endorphins), gastrins, neurohypophyseal (vasopressin).
• Purins – adenosine.