Nervous tissue

Question 1

Neurons

Answer 1

Nerve cells that can be very large
Conscious and unconscious control
Short branched dendrites
Longer single axons
Do not divide
High metabolic rate- die rapidly without O2

Question 2

Multipolar neurons

Answer 2

2 or more dendrites
1 single axon
Most common in CNS
All motor neurons e.g. control and skeletal
Some of the longest

Question 3

Bipolar neurons

Answer 3

1 dentrite
1 axon
Cell body between dendrite and axon
Rare and small
Special sense organs
Relay info from receptor to neuron

Question 4

Unipolar neurons

Answer 4

Continuous dendrite and axon
Cell body off to one side
Sensory nerves
Very long

Question 5

Anaxonic neuron

Answer 5

Rare
Function poorly understood
Cannot distinguish dendrites from axons
Found in brain and special sense organs

Question 6

Neuroglia Functions:

Answer 6

Physical structure of NT
Repairs framework of NT
Undertakes phagocytosis
Nutrient supply to neurons
Regulate interstitial fluid in neural tissue

Question 7

CNS: Astrocytes

Answer 7

Star shaped
Largest
Most numerous
Syncytium
Support
Repair
Maintain environment around neuron
Communicate with neuron via gliotransmitters
Maintain blood brain barrier via endothelium

Question 8

CNS: Oligodendrocytes

Answer 8

Form insulating multilayered myelin sheath around CNS axons
Can myelinate more than one neuron cell’s axon
Accelerate action potential

Question 9

CNS: Microglia

Answer 9

Phagocytic

Protection

Question 10

CNS: Ependymal cells

Answer 10

Produces cerebrospinal fluid
Line CSF filled ventricles in the brain and central canal of the spinal cord.
Single layers of mostly cuboidal cells have cilia and microvilli
CSF mechanical buffer: moves nutrients and waste

Question 11

PNS: Schwann cells

Answer 11

Form insulating myelin sheath around axons

Support and surround several non myelinated axons

Question 12

PNS: Satellite cells

Answer 12

Surround neuron cell bodies

Support fluid exchange