synapses and neurons

Question 1

what does it mean is a neuron is myelinated?

Answer 1

It has a myelin sheath

Question 2

What is a myelin sheath made out of

Answer 2

Schumann cells which are flattened and wrap around the neuron

Question 3

What are the gaps between the myelin sheath on the myelinated neuron called?

Answer 3

Nodes of Ranvier

Question 4

Why did myelinated neurons transmit signals faster?

Answer 4

myelin is an insulator so action potential cannot pass through it, and therefore jumps between the Nodes of Ranvier

Question 5

What is a synapse and how big is it?

Answer 5

The junction between two neurons, the gap is around 20nm wide

Question 6

What are the first 4 l steps of neurotransmission?

Answer 6

1. action potential travels down, presynaptic neuron.
2. Actually potential causes calcium channels to open, allowing calcium 2+ ions to move into the synaptic knob.
3. Calcium ions called synaptic vesicles to move down to the presynaptic membrane.
4. Vesicles experience, exocytosis, and the neurotransmitter is released into the synaptic cleft

Question 7

what are the last 4 steps of neurotransmission?

Answer 7

5. The neurotransmitter defuses from the presynaptic membrane to the postsynaptic membrane.
6. It binds to receptors on the person attic membrane which open sodium ion channels.
7. sodium ions are released into the postsynaptic neuron and when they reach a volume of +40mV a new action potential is made and pass to the next neuron
8. The new and transmitter is then recycled to be reused.