L7: Neurobiology I

Question 1

central nervous system

Answer 1

brain and spinal cord

Question 2

peripheral nervous system

Answer 2

nerves that connect the brain or spinal cord with the body’s muscles, glands, and sense organs

Question 3

both nervous systems are composed of two cell types

Answer 3

neurons and glial cells

Question 4

neurons

Answer 4

cells in the nervous system specialized to initiate, integrate, and conduct electrical signals

Question 5

glia

Answer 5

non-neuronal cells that maintain homeostasis, form myelin, and provide support and protection for neurons

Question 6

glial cells make up __% of the cells in the nervous system

Answer 6

90%

Question 7

four types of glia

Answer 7

astrocytes, microglia, oligodendrocytes, ependymal cells

Question 8

astrocytes

Answer 8

support cells, control extracellular environment

of neurons

Question 9

microglia

Answer 9

immune system of the CNS

Question 10

oligodendrocytes

Answer 10

form the insulating material, myelin

Question 11

ependymal cells

Answer 11

ciliated cells that create a selectively permeable epithelial layer, that separates the CNS fluid compartments

Question 12

olygodendrocytes can extend its processes to up to 50 axons (T/F)

Answer 12

true

Question 13

Schwann cell can wrap multiple neurons (T/F)

Answer 13

false

Question 14

myelin

Answer 14

composed of multiple concentric layers of phospholipid membrane

Question 15

tiny gaps between Schwann cells

Answer 15

Nodes of Ranvier

Question 16

glial cells in PNS

Answer 16

Schwann and satellite cells

Question 17

ganglion

Answer 17

a collection of nerve cell bodies found outside the CNS and appear as knots or swelling along a nerve

Question 18

satellite cells

Answer 18

non-myelinating PNS glial cells that form protective capsules around nerve cells

Question 19

nucleus

Answer 19

a collection of nerve cell bodies inside the CNS

Question 20

membrane between the bones and tissues of the CNS

Answer 20

meninges

Question 21

three layers of meninges

Answer 21

dura, arachnoid, pia matter

Question 22

dura

Answer 22

the thickest, associated with veins

Question 23

arachnoid

Answer 23

loosely tied to the inner membrane, leaving a subarachnoid space between two layers

Question 24

pia matter

Answer 24

thin membrane, associated with arteries

Question 25

a final protective component of the CNS

Answer 25

extracellular fluid that helps cushion the neural tissue

Question 26

extracellular environment for neurons

Answer 26

cerebrospinal fluid and interstitial fluid

Question 27

interstitial fluid lies inside

Answer 27

the pia matter

Question 28

cerebrospinal fluid is found in

Answer 28

the ventricles and the space between the pia matter and the arachnoid membrane

Question 29

cerebrospinal and interstitial fluid communicate

Answer 29

via the leaky junctions of the pial membrane and the ependymal cell layer lining the ventricles

Question 30

the brain floats in

Answer 30

CSF

Question 31

CSF is secreted by

Answer 31

choroid plexus

Question 32

choroid plexus consists of

Answer 32

capillaries and a transporting epithelium

Question 33

choroid plexus cells

Answer 33

selectively pump sodium and other solutes from plasma into the ventricles, creating an osmotic gradient that draws water along with the solutes

Question 34

CSF flows

Answer 34

from the ventricles into the subarachnoid space

Question 35

the rate of fluid

Answer 35

replenish the entire volume of CSF about three times a day

Question 36

CSF is reabsorbed into the blood

Answer 36

at fingerlike projections of the arachnoid membrane called arachnoid villi

Question 37

CSF functions

Answer 37

physical and chemical protection

Question 38

buoyancy of CSF reduces the weight of the brain

Answer 38

nearly 30-fold

Question 39

lighter weight translates into

Answer 39

less pressure on blood vessels and nerves attached to the CNS

Question 40

CSF provides

Answer 40

protective padding

Question 41

choroid plexus is selective about

Answer 41

which substance it transports into the ventricles

Question 42

CSF contains compared to blood

Answer 42

very little protein, no blood cells, Na+ concentrations are similar, K+ concentrations are lower

Question 43

blood brain barrier

Answer 43

acts to maintain selective permeability of substances into the brain

Question 44

blood brain barrier

Answer 44

necessary to isolate the body's main control center from potentially harmful substances (toxins, hormones, ions, neurotransmitters, pathogens)

Question 45

tight junctions

Answer 45

formation of them is stimulated by paracrine signals from adjacent astrocytes whose foot processes surround capillary

Question 46

what cells form tight junctions

Answer 46

endothelial cells in brain capillaries

Question 47

typical capillaries

Answer 47

lack tight junctions resulting in relatively leaky capillary walls

Question 48

transcytosis

Answer 48

the movement of a molecule across an endothelial cell by endocytosis

Question 48

transcytosis

Answer 48

the movement of a molecule across an endothelial cell by endocytosis

Question 48

transcytosis

Answer 48

the movement of a molecule across an endothelial cell by endocytosis

Question 49

hydrophilic molecules can only cross the blood brain barrier

Answer 49

using specific transport proteins

Question 50

transcytosis ___ across capillary endothelial cells in the CNS

Answer 50

does not occur

Question 51

what can pass the blood brain barrier?

Answer 51

hydrophobic molecules, glucose, and amino acids

Question 52

what can't pass the brain blood barrier?

Answer 52

catecholamines, inorganic ions, certain drugs