definitions

Question 1

acquired reflex

Answer 1

a response to a stimulus that has been learnt through practice

Question 2

axon

Answer 2

an extension of the cell body of a nerve cell, carries nerve impulses away from the cell body

Question 3

axon terminal

Answer 3

the end of a branch of the axon

Question 4

bipolar neuron

Answer 4

a neuron with two processes- one axon and one dendrite, arising from opposite sides of the cell body, these neurons are sensory, such as the neurons found in the retina of the eye

Question 5

cell body

Answer 5

the part of a neuron that contains the nucleaus

Question 6

dendrite

Answer 6

an extension of the body of a nerve cell, carries nerve impulses into the cell body

Question 7

extracellular fluid

Answer 7

fluid outside the body cells, includes tissue fluid and blood plasma

Question 8

innate reflex

Answer 8

a response to a stimulus that is acquired genetically and is therefore present at birth

Question 9

interneuron

Answer 9

a nerve cell in the brain or spinal cord that carries messages between other nerve cells, also called association neuron, connector neuron or relay neuron

Question 10

intercellular fluid

Answer 10

the fluid inside cells

Question 11

ion

Answer 11

a charged atom or molecule

Question 12

motor neuron

Answer 12

a nerve cell that carries messages from the brain or spinal cord to effector organs (muscles and glands) also called an effector neuron

Question 13

multipolar neuron

Answer 13

a nerve cell with one axon and many dendrites, the most common type of neuron

Question 14

myelin sheath

Answer 14

a white, fatty sheath that surrounds some nerve fibres

Question 15

myelinated fibre

Answer 15

a nerve fibre that has a myelin sheath

Question 16

nerve

Answer 16

a bundle of nerve fibres

Question 17

nerve fibres

Answer 17

a projection from a nerve cell body with its associated coverings, usually refers to an axon

Question 18

nerve impulse

Answer 18

the electrochemical change that travels along the membrane of a nerve cell, the message carried by a nerve

Question 19

neuromuscular junction

Answer 19

the junction between branches of a motor nerve cell and a muscle fibre, also called the motor end plate

Question 20

neuron

Answer 20

a nerve cell, the basic structural and functional unit of a nervous system

Question 21

neurotransmitter

Answer 21

a molecule that carries a nerve impulse across the small gap between branches of adjacent nerve cells

Question 22

node of Ranvier

Answer 22

a gap in the myelin sheath of a nerve fibre

Question 23

pain receptor

Answer 23

a receptor that is stimulated by damage to tissue

Question 24

pseudounipolar neuron

Answer 24

a neuron with a single process that splits into two, the cell body is to one side of the axon, in humans, such neurons are sensory and carry messages to the spinal cord

Question 25

receptor

Answer 25

a structure that detects a stimulus

Question 26

reflex

Answer 26

a rapid, automatic response to a change in the external or internal environment, tries to restore homoestasis

Question 27

reflex arc

Answer 27

the pathway travelled by nerve impulses from receptor to effector in a reflex

Question 28

Schwann cell

Answer 28

a cell that wraps around a nerve fibre, forming the myelin sheath

Question 29

sense organ

Answer 29

receptors grouped into a discrete organ such as the eye

Question 30

sensory neuron

Answer 30

a nerve cell that carries messages from receptors to the brain or spinal cord, also called a receptor neuron

Question 31

spinal reflex

Answer 31

a reflex carried out by the spinal cord without involvement of the brain

Question 32

spinal reflex arc

Answer 32

the pathway travelled by a nerve impulse from receptors to effector in a spinal reflex

Question 33

stimulus

Answer 33

any changes, internal or external that causes a response

Question 34

synapse

Answer 34

the junction between the branches of adjacent neurons

Question 35

threshold

Answer 35

the potential after which an all or none response occurs

Question 36

touch receptor

Answer 36

a receptor sensitive to touch

Question 37

unipolar neuron

Answer 37

a neuron with a single process, an axon does not occur in humans

Question 38

unmyelinated fibre

Answer 38

a nerve fibre that has no myelin sheath

Question 39

homeostasis

Answer 39

the maintenance of a relatively constant internal environment despite fluctuations in the external environment

Question 40

glycogenesis

Answer 40

the process whereby glucose molecules are chemically combined in long chains to form glycogen molecules

Question 41

glycogenolysis

Answer 41

the process of converting glycogen back to glucose

Question 42

gluconeogenesis

Answer 42

the process of producing glucose molecules from lipids and amino acids

Question 43

herd immunity

Answer 43

a type of group immunity that occurs when such a high proportion of people in a population are immunised that those who are not immune are protected

Question 44

thermoregulation

Answer 44

the regulation of body temperature, the balance of heat gain and heat loss in order to maintain a constant internal body temperature independent of the environmental temperature.

Question 45

metabolic rate

Answer 45

the rate at which energy is released to the body by the breakdown of food

Question 46

what are plasma cells

Answer 46

a cell that develops from B-cell and produces antibodies