Nerve & Muscle

Question 1

Describe the structure of a nerve …

Answer 1

Whole nerve = bundles of fascicles = cell (neurons) = axon

Question 2

Describe the structure of a neuron …

Answer 2

Input zone = dendrites - cell body -axon(tail) - synaptic terminals = output zone

Question 3

What are 3 main subtypes of muscle ?

Answer 3

Cardiac, Smooth, Skeletal

Question 4

Why do we need skeletal muscle system?

Answer 4

Movement, Posture, Thermoregulation

Question 5

What is a electrical gradient?

Answer 5

Ions will move down their electrical gradient; ions require a gradient to move. This will balance the electrical gradient
until there is no net movement.

Question 6

What is a chemical gradient ?

Answer 6

Na+ (sodium) and K+ (potassium) are important ions in our cells. Na+ and K+ will move down their chemical (concentration) gradient. Move from an area of high to low
concentration (down the hill).

Question 7

What is a voltage gated ion channel?

Answer 7

Voltage-gated ion channels are gated by voltage, and are closed when the RPM of the cell is -70 mV

Question 8

What do gradients do?

Answer 8

Prepare neurons for generating action potentials for communication

Question 9

What causes local potential?

Answer 9

Neurotransmitter binds to receptors on the post-synaptic cell, which opens ion channels and can causes a local potential

Question 10

What causes action potential?

Answer 10

If the net threshold at the axon hillock reaches
-60 mV then an action potential will fire

Question 11

What is the role of an axon hillock?

Answer 11

Summates the local potentials > generates action
potential

Question 12

What is a chemically gated ion channel?

Answer 12

channels require a chemical (neurotransmitter) to bind to the receptor for it to be opened