Review Questions

Question 1

As you read this the cells in your eyes are sending info to your brains along what type of neuron.

Answer 1

Afferent Neurons

Question 2

When you are digesting food smooth muscles contract your stomach. Is this controlled by afferent or efferent division of the PNS. How could you describe this in more details

Answer 2

Efferent division, Autonomic Nervous System, Parasympathetic division.

Question 3

What are the parts of a Neuron

Answer 3

a. Pre synaptic terminal, b. Node of Ranvier, c. Collateral axon, d. Golgi apparatus, e. Nucleus, f. Nucleolus, g. Dendrites, h. Mitochondrion, I. Cell body, j. Axon hillock, k. Axon, L. Myelin sheath.

Question 4

What are the six types of neuroglia and their functions?

Answer 4

Shwann cells- insulate PNS axons. Oligodendrocytes- insulate and bind CNS neurons, microglia - fight brain infections with phagocytosis, astrocytes- blood brain barrier, ependymal ciliated and non ciliated secrete and move Cerebrospinal fluid

Question 5

Parts of a nerve

Answer 5

a. Epineurium, b. Fascicle, c. Axon, d. Endoneurium, e parineurium,

Question 6

What is the difference between a sensory nerve a motor nerve and a mixed nerve. What is most common

Answer 6

A sensory neuron only has afferent, motor is efferent. Mix has both. Most are mixed.

Question 7

An axon is covered by an oligodendrocyte is it part of the CNS or pns will it grow a new axon if severed

Answer 7

It is part of the CNS. It will not regenerate.

Question 8

At one point on the axon there is a high concentration of potassium outside the cell on a high concentration of sodium inside the cell is the neuron at rest.

Answer 8

No. It went through repolarization and the sodium potassium exchange pump must switch the two.

Question 9

At one point on the axon there’s a high concentration of sodium outside the cell and a high concentration of potassium inside is the entire neuron at rest

Answer 9

You can’t tell. There is none at that point, but there could be activity somewhere else.

Question 10

Stimulus creates a change in the potential difference between the inside and outside of the cell so that the inside is negative but no action potential is created. what is this called.

Answer 10

Local potential or sub threshold stimulus.

Question 11

What happens in an action potential.

Answer 11

Depolarization: Sodium potassium exchange pump lets sodium in and potential difference goes from -85 to+30. Repolarization: K gates open. K leaves. More - than -85. Then sodium potassium exchange pump works to restore resting potential.

Question 12

What are the specific names of the steps

Answer 12

Depolarization and repolarization

Question 13

What keeps an action potential on an axon from stimulating other action potentials that will travel back towards the cell body

Answer 13

Absolute refractory period.

Question 14

Why do myelinated axons carry action potentials faster than unmyelinated axons?

Answer 14

Saltatory transmission is faster because the action potentials skip from one node of Ranvier to the next.

Question 15

Why do myelinated axons carry action potentials faster than unmyelinated axons?

Answer 15

Saltatory transmission is faster because the action potentials skip from one node of Ranvier to the next.

Question 16

When you cut yourself you feel an instant sharp pain followed a bit later by a dull ache. Why do you get these two different pains and why do they come in that order.

Answer 16

The sharp pain comes from myelinated axons the dull pain comes from unmyelinated axons

Question 17

If you press your finger lightly against an object you feel a certain amount of pressure pressing harder makes you feel more pressure what is the difference in action potentials.

Answer 17

It’s the frequency since they all come at the same strength.

Question 18

Parts of an excitatory synapse

Answer 18

a. Calcium channel, b. Synaptic vesicle, c. Sodium channels, d. Post synaptic neuron, e. Synaptic cleft

Question 19

Monroe signal needs to travel along way through the body it has to have the same properties as destination as it did when it started should the signal be sent along a very long axon or a few shorter ones

Answer 19

Long one

Question 20

The potential difference in a postsynaptic neuron changes from negative 85 ml to -95 millivolts at the point of a synapse what has happened what can you say about the relative amounts of potassium and sodium outside the membrane

Answer 20

Inhibitory synapse. K outside sodium unchanged.

Question 21

12 action potentials are traveling down and acts on in a very short time. They reach a synapse and the postsynaptic neurons only two action potentials through is this an excitatory or inhibitory synapse

Answer 21

Excitatory

Question 22

A bunch of action potentials come from the same neuron is it temporal summation or spatial summation

Answer 22

Temporal cause a bunch came in short time.

Question 23

What are the three kinds of circuits formed by neurons and what are they used for

Answer 23

Diverging-many output one input Converging- many inputs one output
Oscillating- sends signal back to itself.