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Question 1

Glial cell

Answer 1

Glia are smaller more numerous than neurons.

Question 2

Types of glia cells

Answer 2

Astrocytes
Oligodendrocyte 
Schwann cell
Microglial cells
Radial glial cells

Question 3

Astrocyte

Answer 3

Astrocytes wrap around the presynaptic terminals of a group of functionally related axons.
By surrounding a synapse between neurons, an astrocyte shields it from chemicals circulating in the surround.
By taking up ions released by axons and then release long them back, it helps synchronize the activity of the axons, enable them to send messages in waves.
Guide the formation and elimination of synapses.
They remove waste material created when neurons die and control the amount of blood flow to each brain area.
During periods of heightened activity in some brain area, it dilate the blood vessels to bring more nutrient into that area.

Question 4

Oligodendrocyte

Answer 4

Oligodendrocyte in brain and spinal cord build myelin sheaths that surround and insulate certain vertebrate axons. It also supply an axon with nutrients necessary for its functioning.

Question 5

Schwann cell

Answer 5

Schwann cells in periphery of the body build myelin sheaths that surround and insulate certain vertebrate axons. It also supply an axon with nutrients necessary for its functioning.

Question 6

Microglia

Answer 6

Microfilm act as part of the immune system, removing waste material, viruses, and fungi from the brain. They proliferate after brain damage and in most brain diseases. They also contribute to learning by removing the weakest synapses.

Question 7

Radial glia

Answer 7

Radial glia guide the migration of neurons and their axons and dendrites during embryonic development. When embryonic all development finishes, most radial glia differentiate into neurons, and smaller number differentiate into astrocyte and oligodendrocyte.

Question 8

Membrane

Answer 8

Plasma membrane
Most chemicals cannot cross the membrane, but protein channel in the the membrane permit a controlled flow of water, oxygen, sodium, potassium, calcium, chloride, and other important chemicals.

Question 9

Nucleus

Answer 9

The structure that contains the chromosomes.

Question 10

Mitochondria

Answer 10

Perform metabolic activities

It require fuel and oxygen.

Question 11

Ribosome

Answer 11

The sites that the cells synthesizes new protein molecules. Proteins provide building materials for the cell and facilitate chemical reactions.
Some float freely within the cell, but others are attached to the endoplasmic reticulum.

Question 12

Endoplasmic reticulum

Answer 12

A network of thin tubes that transport newly synthesized proteins to other locations.

Question 13

Golgi Apparatus

Answer 13

Wrap or package substances in vesicles for transport to axon terminal
Only in neuron and axon

Question 14

Microtubules

Answer 14

Provide intercellular transport

Only in neuron and axon

Question 15

Multipolar

Answer 15

Most common

One axon and many dendrites.

Question 16

Unipolar neuron

Answer 16

Rare in humans, found in the mesencephalic nucleus of the 5th cranial nerve.

Question 17

Bipolar neuron

Answer 17

One axon and one dendrite. Are found in cochlear and vestibular ganglia, retina and olfactory epithelium

Question 18

Sensory

Answer 18

Afferent
Specialized at one end to be highly sensitive to a particular type or stimulation
Bring information into a structure

Question 19

Motor

Answer 19

Efferent
It’s soma in the spinal cord, receives excitation through its dendrites and conducts impulses along its axon to a muscle
Carries information away from a structure

Question 20

Intrinsic neuron

Answer 20

If a cell’s dendrites and axon are entirely contained with a dingle structure, the cell is an interneuron or intrinsic neuron of that structure.

Question 21

Dendrites

Answer 21

Dendrites are branching fibers that get narrower near their end. The dendrites’ surface is linked with specialized synaptic receptors, at which the dent rite receives information from other neurons. The greater the surface area of a dent rite, the more information it can receive.

Question 22

Dendritic Spines

Answer 22

Many dendrites contain dendritic spines, short out growths that increase the surface area available for synapses.

Question 23

Soma

Answer 23

Cell body
Nucleus, ribosomes, mitochondria
Most of a neuron’s metabolic work occurs here.
Like dendrites, soma is covers with synapses on its surface in many neurons.

Question 24

Axon

Answer 24

The axon conveys an impulse toward other neurons, an organ, or a muscle.
It can range up to more than a meter in length.

Question 25

Myelin sheath

Answer 25

Myelin is a fatty substance that surrounds the axon of some nerve cells, forming a electrically insulating layer.

Question 26

Nodes of ranvier

Answer 26

A gap in the myelin sheath of a neuron.

Question 27

Presynaptic terminals

Answer 27

End bulb or bouton
The end of each axon
Neurotransmitter is packaged inside small vesicles in presynaptic terminal s.

Question 28

Nourishment of neuron

Answer 28

Neuron depend almost entirely on glucose. Because the metabolic pathway that uses glucose requires oxygen, neurons need a steady supply of oxygen. Although the brain constitutes only about 2 percent of the body’s weight, it uses about 20percent of its oxygen.
Glucose is the only nutrient that crosses the blood- brain barrier in large quantities.
To use glucose the body need B1, thiamine.
Prolonged thiamine deficiency, common in chronic alcoholism.
Korsakoff’ syndrome, severe memory impairment.

Question 29

Blood- Brain barrier

Answer 29

It depends on the endothelial cells that form the walls of capillaries. They block viruses, bacteria, and other harmful passage from passage
Oxygen, carbon dioxide cross freely. Water cross through special protein channels. Molecules that dissolve in the fats of the membrane cross easily.

Question 30

Active vs passive transport

Answer 30

While active transport needs energy and work, passive transport does not.
Actively transport into the brain include glucose, amino acids ( building blocks of proteins), purines, choline, a few vitamins, iron, and certain hormones.