Chapter 11

Question 1

a nerve cell that is capable of conducting nerve impulses

Answer 1

neuron

Question 2

the reception, transmission, and integration of nerve impulses by neurons, and the response to these impulses

Answer 2

neural signalling

Question 3

a neuron that carries impulses from sensory receptors to the central nervous system; also called a sensory neuron

Answer 3

afferent neuron

Question 4

a local circuit neuron of the central nervous system that relays impulses between afferent (sensory) and efferent (motor) neurons

Answer 4

interneuron

Question 5

a neuron that carries impulses from the central nervous system to skeletal muscles; also known as a motor neuron

Answer 5

efferent neuron

Question 6

a projection of cytosol that carries signals toward the nerve cell body

Answer 6

dendrite

Question 7

an extension of cytosol that carries nerve signals away from the nerve cell body

Answer 7

axon

Question 8

a non-conducting cell that is important for the structural support and metabolism of nerve cells

Answer 8

glial cell

Question 9

an insulated covering over the axon of a nerve cell

Answer 9

myelin sheath

Question 10

a regularly occurring gap between sections of myelin sheath along the axon

Answer 10

node of Ranvier

Question 11

the body’s coordinating centre for mechanical and chemical actions; made up of the brain and spinal cord

Answer 11

central nervous system (CNS)

Question 12

all parts of the nervous system, excluding the brain and spinal cord; relays information between the central nervous system and other parts of the body

Answer 12

peripheral nervous system (PNS)

Question 13

the component of the peripheral nervous system that receives input through receptors and transmits the input to the central nervous system

Answer 13

afferent system

Question 14

the component of the peripheral nervous system that carries signals away to the effectors (muscles and glands)

Answer 14

efferent system

Question 15

a subdivision of the efferent system (within the PNS); composed of efferent (motor) neurons that carry signals to skeletal muscles in response to external stimuli

Answer 15

somatic system

Question 16

a subdivision of the efferent system (within the PNS); regulates the internal environment

Answer 16

autonomic system

Question 17

one of two subdivisions of the autonomic nervous system; increases energy consumption and prepares the body for action

Answer 17

sympathetic division

Question 18

one of two subdivisions of the autonomic nervous system; stimulates body activities that acquire and conserve energy

Answer 18

parasympathetic division

Question 19

the coordination of the receptor, afferent neuron, interneuron, efferent neuron, and effector in response to a stimulus

Answer 19

neural circuit

Question 20

a neural circuit that travels through the spinal cord but does not require the coordination of the brain; allows for reflex actions

Answer 20

reflex arc

Question 21

a functional connection between neurons or between neurons and effectors

Answer 21

synapse

Question 22

a synapse in which a neurotransmitter moves from a presynaptic cell to a postsynaptic cell through the synaptic cleft

Answer 22

chemical synapse

Question 23

a chemical that is released from vesicles into synapses to facilitate nerve signal transmission

Answer 23

neurotransmitter

Question 24

the tiny gap between presynaptic and postsynaptic cells in a chemical synapse, across which the neurotransmitter diffuses

Answer 24

synaptic cleft

Question 25

a synapse in which the presynaptic cell makes direct contact with the postsynaptic cell, allowing current to flow via gap junctions between the cells

Answer 25

electrical synapse

Question 26

the electrical potential of a membrane, which is caused by an imbalance of charges on either side of the membrane

Answer 26

membrane potential

Question 27

a protein embedded in the plasma membrane that allows ions to pass through it

Answer 27

ion channel

Question 28

the voltage difference across a nerve cell membrane of an unstimulated neuron; usually negative

Answer 28

resting potential

Question 29

the voltage difference across a nerve cell membrane when the nerve is excited

Answer 29

action potential

Question 30

the potential at which an action potential is generated by a neuron

Answer 30

threshold potential

Question 31

the period of time during which the threshold required for the generation of an action potential is much higher than normal

Answer 31

refractory period

Question 32

three layers of connective tissue that surround and protect the brain and spinal cord

Answer 32

meninges

Question 33

circulating fluid that surrounds the membranes of the brain and spinal cord; provides neural connection to the endocrine system

Answer 33

cerebrospinal fluid

Question 34

the tissue of the brain and spinal cord, where the cell bodies and dendrites of neurons are located

Answer 34

grey matter

Question 35

the tissue of the brain and spinal cord, composed primarily of axons of neurons; in the spinal cord, it surrounds the grey matter

Answer 35

white matter

Question 36

the hindbrain region that connects the spinal cord to the cerebellum; important in autonomic nerve control

Answer 36

medulla oblongata

Question 37

the hindbrain region that is involved in muscle movement and balance

Answer 37

cerebellum

Question 38

the brain region that transfers nerve signals between the cerebellum and the medulla

Answer 38

pons

Question 39

the brain region that is involved in motor activities and sensory information; the largest and most developed region of the brain

Answer 39

cerebrum

Question 40

the outermost layer of the cerebral hemispheres

Answer 40

cerebral cortex

Question 41

the brain region that interprets sensory input and signals the cerebrum

Answer 41

thalamus

Question 42

a barrier formed by tight junctions between endothelial cells in the capillaries in the brain that blocks the movement of most substances into the brain via the bloodstream

Answer 42

blood-brain barrier

Question 43

the 31 pairs of nerves within the somatic system that transmit motor, sensory, and autonomic signals between the spinal cord and the rest of the body

Answer 43

spinal nerves

Question 44

the 12 pairs of nerves within the parasympathetic division of the autonomic system, which emerge directly from the brain and serve the head, neck, and body trunk

Answer 44

cranial nerves

Question 45

a band of grey matter in the spinal cord that, when stimulated, produces a neurotransmitter that communicates with an injured region of the body; a simultaneous signal to the brain results in the perception of pain

Answer 45

substantia gelatinosa (SG)

Question 46

the tendency for some sensory receptors to become less sensitive when stimulated repeatedly

Answer 46

sensory adaptation

Question 47

a negative feedback mechanism that attempts to maintain blood pressure

Answer 47

renin-angiotensin-aldosterone pathway