DHUBS1 - week 3

Question 1

what are the major organs of the nervous system?

Answer 1

brain
spinal cord
peripheral nerves
sense organs

Question 2

what is the function of the nervous system?

Answer 2

maintain homeostasis by controlling organ systems and behavioural drives
cognition and memory
provides and interpruts sensory infromation about external conditions
contorl of skeletal muscles

Question 3

what are the basic parts of neurons?

Answer 3

cell body or soma: contains the cell nucleus and other neurons
axon: carries infromation toward other neurons
dendrites: recieves infromation form other neurons

Question 4

classification of nerurons (3 types of neurons)

Answer 4

sensory neurons: deliver infromation from sensory receptors to the CNS
moter neurons: deliver information about movement from the CNS
interneurons: form connections with other neurons

Question 5

what are the three ways information travels within the nervous system?

Answer 5

neurotransmission
membrane potential
action potential

Question 6

describe action potential

Answer 6

is a sudden rise and fall in membrane potential of a neuron in response to a stimulus. It is a temporary shift in the neuron’s resting membrane potential when it sends information down the axon away from the cell body.

Question 7

describe the 4 steps of action potential

Answer 7

1. a graded polarisation brings an area of exitable membrane to threshold (-60mV)
2. voltage-gated sodium channels open and sodium ions move into teh cells. the transmembrane potential rises to +30mV
3. sodium channels close, voltage-gated potassium channels open, and potassium ions move out of the cell. repolarisation begins.
4. potassium cahnnels close, and both sodium and pottasium channels return to theri normal states

Question 8

what are the four major brain regions?

Answer 8

cerebrum
cerebellum
diencephalon: thalamus, hypothalamus, ineal gland and pituitary gland
brain stem: mesencephalon, pones, medulla oblongata

Question 9

what is the function of the central nervous system?

Answer 9

integrating and processing information
coordinating sensory information and commands
learning and memory

Question 10

what is the function of the peripheral nervous system?

Answer 10

carries sensory information from the body to the CNS
carries commands from the CNS to the body

Question 11

the peripheral nervous system is divided into two, what are they?

Answer 11

automnomic system: controls unconcious functions (heart rate etc…) includes glands, smooth muscle, cardic muscle, and adipose tissue
somatic nervous system: ‘pertaining to the body’ includes skeletal muscles, skin and joints

Question 12

the somatic and autonomic nervous system consist of two componenets, what are they?

Answer 12

afferent - conveys sensory information from the external envrinoment to the CNS
efferent - conveys motor information from the CNS to end organ

Question 13

describe the withdrawl reflex

Answer 13

Arrival of stimulus and activation of receptor
Activation of a sensory neuron
Information processing in the CNS
Activation of a motor neuron
Response by a peripheral effector

Question 14

Name 4 elements in the human body and their % of total body weight

Answer 14

Oxygen (65)
Carbon (18.6)
Hydrogen (9.7)
Nitrogen (3.2)

Question 15

what does the neuroglia consist of in the CNS

Answer 15

astrocytes
edenymal cells
oligodendrocytes
microgolia

Question 16

what does the neuroglia consist of ine the PNS

Answer 16

satellite cells
schwann cells
myelin

Question 17

what are the functions for the basic parts of a neuron?

Answer 17

cell body: contains nucleus and other organelles
dendrites: recieves infromation from other neurons
axon: carries infromation towards other neurons or cells
axon hillock: start of the axon
axon terminal: end of axon

Question 18

what is the parasympathatic nervous system?

Answer 18

rest and digest

Question 19

what is the sympathatic nervous system

Answer 19

fight or flight