Nervous Tissues

Question 1

What are the 3 parts of neurons

Answer 1

Dendrites, cell body, and axons

Question 2

It receives messages from other neurons

Answer 2

Dendrites

Question 3

Contains the genetic information determining cell function

Answer 3

Cell body

Question 4

Conducts electrical impulses

Answer 4

Axons

Question 5

Brain and spinal cord

Answer 5

CNS

Question 6

Nerves or nerve fiber

Answer 6

PNS

Question 7

It is a bundle of central axons

Answer 7

Nerve tract

Question 8

Bundle of peripheral axons

Answer 8

Nerve fiber

Question 9

It has myelinated axons

Answer 9

White matter

Question 10

It has cell bodies and unmyelinated

Answer 10

Gray matter

Question 11

Excitable cells that transmit electrixal signals

Answer 11

Neurons

Question 12

Cells that surround and wrap neurons
-maintain homeostasis, form myelin and provide support for neurons
-non neuronal in CNS
- do not produce electrical impulse PNS

Answer 12

Neuroglia

Question 13

It is around invidividual axon

Answer 13

Endoneurium

Question 14

It is around individual fascicle

Answer 14

Perineurium

Question 15

It is around entire nerve

Answer 15

Epineurium

Question 16

It is afferent, arrives or bring stimuli
- info is transmitted from sensory receptor to CNS

Answer 16

Sensory neuron

Question 17

It is efferent, exits or carry response
-info is from CNS to the effector cell

Answer 17

Motor neuron

Question 18

It is found between sensory and motor which acts as mediator (bridge of communication)

Answer 18

Interneuron

Question 19

It only has one axon

Answer 19

Unipolar

Question 20

It has one axon and one dendrite

Answer 20

Bipolar

Question 21

One axon but dendrites not coming from soma (cell body)

Answer 21

Pseudounipolar

Question 22

Has many dendrites and one axon

Answer 22

Multipolar

Question 23

What are the characteristics of ependymal cells

Answer 23

-Forms epithelial lining of ventricles (cavities) in the brain and central canal of spinal cord
- production and regulation of CSF
- apical surface covered of cilia that circulates CSF around CNS and has microvilli to absorb CSF

Question 24

Produces myelin sheath

Answer 24

Oligodendrocyte

Question 25

What is astrocytes

Answer 25

Specialized glial cells that outnumber neurons -structural support insulating receptive surfaces, and buffer extracellular compartment -during inflammation and injury they wall off damaged areas

Question 26

Specialized macrophages that remove damaged neurons and infections -maintain health of CNS -professional innate phagocytes

Answer 26

Microglial cells

Question 27

Surrounds neurons in PNS, support and protect

Answer 27

Satellite cells

Question 28

Covers the neuron in myelin and alsi maintain nerve fibers *PNS*

Answer 28

Schwann cells

Question 29

Why RMP is negative?

Answer 29

K+ positive leaks from inside that geneeate negative charge inside, so Na+ and K+ do not attain equilibrium

Question 30

Steps of nerve conduction

Answer 30

1. Neurons have resting membrane potential (-70 mV) > polarization 2. Neurons are surrounded by high concentration of Na+ 3. The inside of neuron has some positively K+ ions and many charged ions (proteins and sulfates) 4. Combination of Na+ environment outside and K+ positive inside = resting membrane potential

Question 31

Also called as action potentials - a self propagating wave of electrical disturbance -electrochemical signal

Answer 31

Nerve impulses

Question 32

Steps of nerve conduction: the action potential

Answer 32

1. Dendrites are stimulated by axons of other neurons 2. Na+ ions flow into the neuron by action of ion channels - membrane voltage positive = depolarization 3. If the partial depolarization reaches -.65 mV (Ap threshold) the neurons fire

Question 33

Na influx

Answer 33

Depolarization

Question 34

K efflux

Answer 34

Repolarization

Question 35

Na+ and K+ pump

Answer 35

Recharging

Question 36

What are the effects of neurotransmitters?

Answer 36

1. Excitatory neurotransmitters depolarize the postsynaptic cell membrane by stimulating the inflow of sodium ions 2. Hyperpolarize the membraine by stimulating ion channels to allow K+ ions flow out, inhiniting neuron firing

Question 37

Involved in memory and muscle activity

Answer 37

Acetylcholine (ACh)

Question 38

Enhances mood, eating, sleep, and sexual behavior

Answer 38

Serotonin

Question 39

An excitatory transmitter

Answer 39

Dopamine

Question 40

Reduce pain and increase feeling of well being

Answer 40

Endorphins