nervous system

Question 1

structure and functions of the central nervous system

Answer 1

• brain and the spinal cord
• enables the brain to communicate with the rest of the body by conveying messages from the brain to the PNS, and from the PNS to the brain

Question 2

structure and functions of the peripheral nervous system

Answer 2

• has 2 subdivisions: somatic and autonomic
• communicates info from the body’s organs, glands and muscles to the CNS
• communicates info from the CNS to the body’s organs glands and muscles via motor neurons

Question 3

autonomic functions

Answer 3

controls self-regulated actions of organs and glands

Question 4

somatic functions

Answer 4

controls voluntary movement of skeletal muscles

Question 5

neurons in somatic

Answer 5

motor and sensory

Question 6

2 systems in autonomic

Answer 6

• sympathetic: is like an emergency system that readies the body for action eg. running away
• parasympathetic: maintain automatic day to day bodily functions eg. digestion and heartbeat

Question 7

role of motor neurons

Answer 7

communicates messages from the CNS to particular muscles that an organism intends to move at any particular time

Question 8

role of sensory neurons

Answer 8

carry info from the body and from the outside world into the CNS

Question 9

afferent and efferent neurons

Answer 9

• afferent are sensory neurons that carry nerve impulses towards the CNS
• efferent are motor neurons that carry nerve impulses away from CNS to muscles

Question 10

what are interneurons

Answer 10

neurons in the brain that enable communication between sensory or motor neurons and the CNS

Question 11

list structures of a neuron

Answer 11

dendrites, soma, axon, myelin, terminal buttons, synapse

Question 12

dendrites function

Answer 12

receive info from other neurons or sensory receptors via synapses and deliver this to the soma

Question 13

soma function

Answer 13

is the cell body - controls the metabolism and maintenance of the cell

Question 14

axon function

Answer 14

a nerve fiber that carries info away from the soma toward axon terminals. Terminal buttons inside axon terminals at the end of each axon- turns the message from an electrical impulse to a chemical

Question 15

myelin function

Answer 15

fatty substance that covers the axon to insulate it from the surrounding fluid and from other neurons

Question 16

define glial cells

Answer 16

cells that are not part of the neuron but have an important role in supporting neurons

Question 17

glial cells function

Answer 17

• to surround neurons and hold them in place
• supply nourishment and oxygen to neurons
• remove dead neurons
• insulate one neuron from another and increase the speed of transmission of nerve impulses

Question 18

types of glial cells in the CNS

Answer 18

astrocytes- structural support.
oligodendroglia- insulates by forming myelin sheath around axons.
microglia- protects neurons from foreign substances.

Question 19

types of glial cells in the PNS

Answer 19

Schwann cells- form myelin sheath around axons

Question 20

what are 3 functions of the nervous system

Answer 20

• receive information
• process information
• respond to information

Question 21

what is a neuron

Answer 21

individual nerve cells that are specialised to receive, process and transmit information