Human Nervous System

Question 1

What are the two important parts of the nervous system?

Answer 1

Peripheral Nervous System (PNS) and Central Nervous System (CNS)

The PNS controls voluntary and involuntary actions, while the CNS processes sensory information.

Question 2

What is the primary function of the Central Nervous System (CNS)?

Answer 2

Information synthesizing

The CNS regulates organ function, high-level thought, and purposeful body movement.

Question 3

What does the Peripheral Nervous System (PNS) control?

Answer 3

Volitional (somatic) and non-volitional (autonomic) behaviours

It uses cranial and spinal nerves to carry signals necessary for survival.

Question 4

What are the two divisions of the autonomic nervous system?

Answer 4

Sympathetic and parasympathetic divisions

The sympathetic division prepares the body for stress, while the parasympathetic division restores routine functions.

Question 5

What is the role of the sympathetic nervous system?

Answer 5

Prepares the body for stress-related activities

It triggers the fight-or-flight response in fear-inducing situations.

Question 6

What is the role of the parasympathetic nervous system?

Answer 6

Restores and calms down physiological responses

It maintains homeostasis and routine operations.

Question 7

What are the main components of the Central Nervous System?

Answer 7

Brain, brainstem, and spinal cord

Each component performs various tasks crucial for body function.

Question 8

What is the largest part of the Central Nervous System?

Answer 8

The brain

It is responsible for sensation, perception, thinking, awareness, emotions, and planning.

Question 9

What is the function of the limbic system?

Answer 9

Regulates emotions

It includes structures such as the hippocampus and amygdala.

Question 10

What are the four major parts of a neuron?

Answer 10

Dendrites, cell body (soma), axon, terminal boutons

Each part plays a crucial role in information transmission.

Question 11

What is an action potential?

Answer 11

An all-or-nothing event that occurs when a neuron fires an impulse signal

It involves a change in the charge of the cell’s membrane.

Question 12

What must a neuron reach to initiate an action potential?

Answer 12

Threshold of excitation

This is the change in membrane potential that excites the neuron.

Question 13

What are EPSP and IPSP?

Answer 13

Excitatory postsynaptic potential and inhibitory postsynaptic potential

EPSP causes depolarization, while IPSP causes hyperpolarization of the neuron’s membrane.

Question 14

What is the function of the cerebellum?

Answer 14

Coordinates actions without conscious awareness

It plays a key role in motor movement coordination and balance.

Question 15

What does the brainstem oversee?

Answer 15

Basic life support functions such as breathing, digestion, and heartbeat

It operates without conscious effort.

Question 16

What type of neurons carry information from the CNS to the muscles?

Answer 16

Efferent neurons

Efferent means ‘moving away from’.

Question 17

What type of neurons carry sensory information to the CNS?

Answer 17

Afferent neurons

Afferent means ‘moving toward’.

Question 18

Fill in the blank: The ________ is a layer of fatty tissue surrounding the axon of a neuron.

Answer 18

myelin sheath

It helps to insulate the neuron and allows for faster transmission of electrical signals.

Question 19

What is the corpus callosum?

Answer 19

A thick bundle of axons connecting the two cerebral hemispheres

It facilitates communication between the left and right sides of the brain.

Question 20

True or False: The left side of the brain controls sensory and motor functions of the left side of the body.

Answer 20

False

The brain is contralateral; the left side controls the right side of the body and vice versa.

Question 21

What is the function of the medulla oblongata?

Answer 21

Processes breathing, digestion, heart and blood vessel function

It is part of the brainstem.

Question 22

What is the refractory period in neurons?

Answer 22

A time during which a neuron is incapable of firing because the excitable membrane must return to a resting state.

Question 23

What are the two subsets of the refractory period?

Answer 23

• Absolute refractory period (ARP)
• Relative refractory period (RRP)

Question 24

What happens during the absolute refractory period (ARP)?

Answer 24

The neuron cannot send a new impulse because sodium channels are inactive.

Question 25

What is the relative refractory period (RRP)?

Answer 25

A period following the ARP when a neuron can respond to a stimulus but requires a stronger than normal stimulus.

Question 26

What is the synaptic cleft?

Answer 26

A small space between adjacent neurons that allows nerve impulses to pass from one neuron to another.

Question 27

What are neurotransmitters?

Answer 27

Chemicals that relay signals across synapses between neurons.

Question 28

What role do neurotransmitters play at the synapse?

Answer 28

They are released when the action potential reaches the end of the axon and travel across the synaptic space to bind to receptors on neighboring neurons.

Question 29

What happens if neurotransmitters are not accepted by receptor sites?

Answer 29

They must be removed from the synapse to allow for the next potential stimulation of the neuron.

Question 30

What is the action potential?

Answer 30

A transient all-or-nothing transmission of impulse conducted down the axon when the membrane potential reaches the threshold of excitation.

Question 31

What does the axon do?

Answer 31

Sends information to another neuron or to muscles and glands.

Question 32

How do electrical signals travel down the axon?

Answer 32

Through changes in the electrical charge of the axon, jumping from node to node.

Question 33

What is the resting membrane potential?

Answer 33

A state where the interior of the neuron contains a greater number of negatively charged ions than the area outside the cell.

Question 34

What is the function of acetylcholine (ACh)?

Answer 34

Stimulates muscle contractions and regulates memory, sleeping, and dreaming.

Question 35

What psychological condition is associated with a deficiency of acetylcholine?

Answer 35

Alzheimer’s disease.

Question 36

What is dopamine involved in?

Answer 36

Movement, motivation, and emotion; it produces feelings of pleasure.

Question 37

What is associated with low levels of serotonin?

Answer 37

Seasonal depression.

Question 38

What is the main function of GABA (gamma-aminobutyric acid)?

Answer 38

It is the major inhibitory neurotransmitter in the brain.

Question 39

What does an agonist drug do?

Answer 39

Mimics the effects of a neurotransmitter.

Question 40

What is an antagonist drug?

Answer 40

A drug that reduces or inhibits the normal effects of a neurotransmitter.

Question 41

Fill in the blank: The _______ is the part of the peripheral nervous system that controls involuntary functions.

Answer 41

autonomic nervous system

Question 42

What is the main role of the somatic nervous system?

Answer 42

Controls conscious and voluntary activities.

Question 43

What is the corpus callosum?

Answer 43

The nerve fibre that connects the left and right hemispheres of the brain.

Question 44

What is the difference between EPSP and IPSP?

Answer 44

* EPSP: depolarizing current that makes the membrane potential more positive * IPSP: hyperpolarizing current that makes the membrane potential more negative

Question 45

What is the significance of the Node of Ranvier?

Answer 45

It allows the electrical charge to jump from segment to segment along the axon.

Question 46

What happens during neurotransmitter reuptake?

Answer 46

Neurotransmitters in the synapse are reabsorbed into the transmitting terminal buttons.

Question 47

What are endorphins known for?

Answer 47

Natural pain relievers related to compounds found in opium, morphine, and heroin.

Question 48

What effect does excess glutamate have?

Answer 48

Can cause overstimulation, migraines, and seizures.

Question 49

What does a neuron respond to?

Answer 49

A very intense stimulation.

Question 50

What is the resting membrane potential?

Answer 50

A state in which the interior of the neuron contains a greater number of negatively charged ions than the area outside the cell.

Question 51

What is the function of the retina?

Answer 51

It is a cell layer in the back of the eye containing photoreceptors.

Question 52

What is the soma in a neuron?

Answer 52

The cell body of a neuron that contains the nucleus and genetic information and directs protein synthesis.

Question 53

What does the somatic nervous system control?

Answer 53

Conscious and voluntary activities and serves as a relay of sensory and motor information to and from the central nervous system.

Question 54

What is the spinal cord?

Answer 54

A section of the central nervous system that connects the brain and the brainstem to all major nerves in the body.

Question 55

What is the role of the sympathetic nervous system?

Answer 55

It prepares the body for stress-related activities.

Question 56

What is a synapse?

Answer 56

A process whereby neurons use electrical and chemical messages to communicate with each other at the synaptic cleft.

Question 57

What is the synaptic (gap) cleft?

Answer 57

The small space between the presynaptic terminal button of one neuron and the postsynaptic dendrite of another adjacent neuron.

Question 58

What part of the brain is involved in auditory and olfactory processing?

Answer 58

Temporal lobe.