Week 4 - The Nervous System

Question 1

define processes

Answer 1

the long extensions that connect neurons to each other

Question 2

define cell body (soma)

Answer 2

nucleus and ribosomes = genetic info and protein synth

Question 3

define dendrites

Answer 3

receive incoming info from other neurons

Question 4

define dendritic spines

Answer 4

increase surface area of dendrites

Question 5

define axon

Answer 5

extends from the cell body and carries outgoing signals to target cells

Question 6

define axon terminal

Answer 6

releases neurotransmitters from the axon

Question 7

define varicosties

Answer 7

bulging areas where signals can be released

Question 8

define myelin

Answer 8

covers many neurons and consists of many layers of highly modified plasma membrane

Question 9

define oligodendrocytes

Answer 9

the material that myelin is made of in the CNS

Question 10

define Schwann cells

Answer 10

glial cells in the PNS, form individual myelin sheaths at regular intervals

Question 11

define Nodes of Ravier

Answer 11

spaces between adjacent section of myelin

Question 12

what is the role of the myelin sheath ?

Answer 12

speeds up conduction of electrical signals along axon

Question 13

what are the 3 types of neurons ?

Answer 13

• afferent
• efferent
• interneurons

Question 14

define afferent neurons

Answer 14

convey info from tissue and organs TOWARDS CNS

Question 15

define efferent neurons

Answer 15

convey information AWAY from CNS to effector cells

Question 16

define interneurons

Answer 16

• connect neurons within the CNS

- 99% of all neurons

Question 17

define synapse

Answer 17

specialised junction between 2 neurons

Question 18

how are signals transmitted ?

Answer 18

through neurotransmitters

Question 19

define presynaptic neuron

Answer 19

conducts a signal TOWARDS a synapse

Question 20

define postsynaptic neuron

Answer 20

conducts signals AWAY from synapse

Question 21

define glial cells

Answer 21

• surround axon and dendrites

- provide physical and metabolic support

Question 22

what are the 5 types of glial cells ?

Answer 22

• oligodendrocyte
• astrocyte
• microglia
• ependymal cells
• schwann cells

Question 23

define nerves

Answer 23

group of axons travelling together to and from the PNS

Question 24

define ganglia

Answer 24

group of neuron cell bodies in the PNS

Question 25

define nuclei

Answer 25

group of neuron cell bodies in the CNS

Question 26

what are the 3 different regions of the brain ?

Answer 26

- forebrain - midbrain - hindbrain

Question 27

what are the subdivisions of the forebrain ?

Answer 27

- cerebrum | - diencephalon

Question 28

what are the subdivisions of the midbrain ?

Answer 28

remains single major division

Question 29

what are the subdivisions of the hindbrain ?

Answer 29

- pons - medulla oblongata - cerebellum

Question 30

define cerebrum

Answer 30

- upper most part of the brain | - L and R hemispheres

Question 31

what are the 3 division of the cerebrum ?

Answer 31

- cerebral cortex - basal ganglia - limbic system

Question 32

define cerebral cortex

Answer 32

- outer shell of grey matter - 4 lobes - 6 layers of pyramidal / nonpyramidal cells

Question 33

what are the 4 lobes of the cerebral cortex ?

Answer 33

- frontal - parietal - occipital - temporal

Question 34

what is the role of the cerebral cortex ?

Answer 34

- convert basic info into meaningful images | - convey info about specific events

Question 35

define pyramidal cells

Answer 35

send their axons to other parts of CNS

Question 36

define nonpyramidal cells

Answer 36

receive input

Question 37

define basal ganglia

Answer 37

- groups of grey matter - movement and posture - complex behaviour

Question 38

define limbic system

Answer 38

- grey and white matter - learning - endocrine function - emotional experience

Question 39

define diencephalon

Answer 39

contains the thalamus, hypothalamus and epithalamus

Question 40

define thalamus

Answer 40

- several large nuclei - synaptic relay stations - integrating centres - focusing attention e.g. background noise during conversation

Question 41

define hypothalamus

Answer 41

- numerous different nuclei - eating, drinking - connected to pituitary gland

Question 42

define epithalamus

Answer 42

- small mass of tissue - includes pineal gland - controls circadium rhythms

Question 43

define midbrain

Answer 43

- motor movement - movements of the eye - auditory and visual processing

Question 44

define hindbrain

Answer 44

- motor functions - cardiovascular control - respiratory control

Question 45

how many pairs of nerves are in the PNS ?

Answer 45

43

Question 46

how many pairs of nerves are cranial nerves ?

Answer 46

12