Synaptic transmission

Question 1

Synaptic Transmission

Answer 1

The process by which neurons communicate with each other and facilitate changes in the brain.

Question 2

Synaptic transmission: Process

Answer 2

-When an AP reaches the end of an axon/axon terminal, the electrical signal is converted to a chemical signal. synaptic vesicles at the presynaptic terminal release neurotransmitters which diffuse accross the synaptic cleft and bind to specialised receptors on the postsynaptic neuron

Question 3

Neurotransmitters

Answer 3

Chemical messengers neurons use to communicate with each other, cause changes within cells and play important functions

Question 4

Otto Loeiwi (1921)

Answer 4

Demonstrated the effect of neurotransmitters
-2 frog hearts in water, one w vagus nerve intact, stimulated vagus nerve causing the heart to slow, the other heart also slowed-shows chemical communication

Question 5

Small neurotransmitters

Answer 5

-Packed into vesicles in the presynaptic neuron by terminals golgi complex

Question 6

Large neurotransmitters

Answer 6

-Large (peptide) neurotransmitters-cytoplasm of cell body, packed into vesicles, transported to terminals by microtubules

Question 7

Voltage-Activated calcium channels

Answer 7

Facilitate the release of neurotransmitters, when an action potential is produced the voltage causes calcium channels to open allowing calcium into the cell, causing the presynaptic membrane to empty its contents into the synaptic cleft.

Question 8

Neurotransmitter dependent ion channels

Answer 8

When neurotransmitters bind to receptors, this causes ion channels to open changing the membrane potential potentially causing an action potential (known as postsynaptic potentials)

Question 9

What can postsynaptic potentials be

Answer 9

Can be exhibitory causing depolarisation or inhibitory causing hyperpolarisation depending on wether a sodium or potassium channel is opened.

Question 10

Exhibitory neurotransmitters

Answer 10

Increase activity in the cell, occurs when postsynaptic potential opens a sodium channel, causing depolarisation

Question 11

Inhibitory neurotransmitters

Answer 11

Decrease cell activity, occurs when postsynaptic potential opens a potassium channel causing hyperpolarisation

Question 12

Inhibitory postsynaptic potential

Answer 12

Occurs when postsynaptic potential opens a potassium channel causing hyperpolarisation

Question 13

Exhibitory postsynaptic potential

Answer 13

Occurs when a postsynaptic potential opens a sodium channel causing depolarisation.