nervous tissue: exam 4(final)

Question 1

what is the function of neurons?

Answer 1

they are signal sending and receiving cells

Question 2

what is the cell body of a neuron?

Answer 2

it contains the nucleus, does basic cell functions, and can receive signals (neurons)

Question 3

what are dendrites?

Answer 3

they are branched structures off of cell body, they receive signals. (neurons)

Question 4

what is the funnel shaped area of a neuron that extends from the cell body to axon, signals to be sent start here?

Answer 4

axon hillock (neurons)

Question 5

what is an axon?

Answer 5

it is a long projection that extends out to contact other cells, signals travel down axon (neurons)

Question 6

what are the expanded regions at the end of an axon that are the contact points with other cells and pass signals to other cells?

Answer 6

axon terminals (neurons)

Question 7

what is the myelin sheath?

Answer 7

it is a coating of fat on axon, made by other cells, its purpose is to speed up signals. (neurons)

Question 8

what are bare patches of axon in the myelin sheath?

Answer 8

nodes (neurons)

Question 9

what are multipolar neurons?

Answer 9

they have lots of dendrites, one axon, multi purpose

Question 10

what are bi polar neurons?

Answer 10

they have one fat dendrite (may have branches), and one axon, always sensory.

Question 11

what are unipolar neurons?

Answer 11

cell body is off to the side of one long combined axon/dendrite, these are all sensory, their job is to pass the signals to one place to another

Question 12

what is neuroglia?

Answer 12

all support cells that help out neurons

Question 13

what are astrocytes?

Answer 13

part of CNS neuroglia- (star cells) have lots of projections, some projections touch the neurons, help keep neurons with metabolism. some projections cover entire surface of CNS capillaries- creates blood brain barrier. anything in blood must filter through the astrocytes to get to brain tissue. (neuroglia)

Question 14

what are oligodendrocytes?

Answer 14

few projection cells, projections wrap axons of neurons to form the myelin sheath, one oligodendrocyte can wrap a small part of multiple axons (neuroglia CNS)

Question 15

what crawl around the CNS looking for pathogens then turn into macrophages and eat the pathogens (phagocytosis), and are immune cells?

Answer 15

microglia (neuroglia)

Question 16

what lines the hollow spaces in the CNS, they produce the cerebral spinal fluid, they have cilia that moves the fluid?

Answer 16

ependymal cells (neuroglia)

Question 17

what type of cells are on the cell body of neuron, support metabolism of neuron?

Answer 17

satellite cells (PNS neuroglia)

Question 18

what are neurolammocytes also know as shwann cells?

Answer 18

they form the myelin sheath of axons in the PNS, each shwann cell is on one axon only (doesn’t reach out to other axons)

Question 19

what is a nerve fiber?

Answer 19

it is one axon + its myelin sheath

Question 20

what is a nerve?

Answer 20

a bundle of nerve fibers in the PNS wrapped in connective tissue

Question 21

what is ganglia?

Answer 21

collection of cell bodies in PNS wrapped in connective tissue

Question 22

what is a tract?

Answer 22

its a bundle of nerve fibers in CNS not wrapped in connective tissue

Question 23

what is nucleus of neurons?

Answer 23

collections of cell bodies in CNS no connective tissue

Question 24

what is gray matter?

Answer 24

it is a large amount of cell bodies in the CNS

Question 25

what is white matter?

Answer 25

it is a large area of axons in CNS

Question 26

what is a synapse?

Answer 26

it is a connection between neurons, axon terminals of one cell come into contact with dendrites a cell body of another cell, signals are passed across synapses