Control and Coordination Concept 1 Vocabulary

Question 1

Soma (cell body)

Answer 1

The main part of a neuron that contains the nucleus and other organelles, responsible for maintaining the cell’s metabolic activities.

Question 2

Dendrites

Answer 2

Branch-like extensions of a neuron that receive incoming signals from other neurons or sensory receptors.

Question 3

Axon

Answer 3

A long, slender projection of a neuron that conducts electrical impulses away from the cell body towards other neurons, muscles, or glands.

Question 4

Ganglion

Answer 4

A cluster of nerve cell bodies located outside the central nervous system (CNS), typically associated with sensory neurons.

Question 5

Nerve

Answer 5

A bundle of axons (nerve fibers) enclosed within connective tissue, which transmits electrical impulses between the central nervous system (CNS) and other parts of the body.

Question 6

Axon terminal

Answer 6

The end of an axon where neurotransmitters are released to communicate with adjacent neurons or effector cells.

Question 7

Myelin sheath

Answer 7

A fatty, insulating layer formed by Schwann cells (in the peripheral nervous system) or oligodendrocytes (in the central nervous system) around axons, which increases the speed of nerve impulse transmission.

Question 8

Nodes of Ranvier

Answer 8

Gaps in the myelin sheath along the axon where action potentials are regenerated during saltatory conduction.

Question 9

Sensory neurons

Answer 9

Neurons that transmit sensory information from sensory receptors to the central nervous system (CNS).

Question 10

Motor neurons

Answer 10

Neurons that transmit signals from the central nervous system (CNS) to muscles or glands, causing them to contract or secrete.

Question 11

Interneurons

Answer 11

Neurons located entirely within the central nervous system (CNS) that integrate and relay signals between sensory and motor neurons.

Question 12

Resting membrane potential

Answer 12

The difference in electrical charge across the membrane of a neuron when it is not transmitting a signal, typically around -70 millivolts (mV).

Question 13

Graded potential

Answer 13

Small changes in membrane potential that occur in dendrites or the cell body, which may either depolarize (excitatory) or hyperpolarize (inhibitory) the neuron.

Question 14

Threshold

Answer 14

The membrane potential at which an action potential is initiated, typically around -55 millivolts (mV).

Question 15

Action potential

Answer 15

A rapid and transient change in membrane potential that propagates along the axon of a neuron, allowing for long-distance communication.

Question 16

Nerve impulse

Answer 16

The transmission of an action potential along the length of a neuron’s axon.

Question 17

Depolarization

Answer 17

The temporary reversal of membrane potential from negative to positive due to the influx of positively charged ions (e.g., sodium ions) into the neuron.

Question 18

Repolarization

Answer 18

The restoration of the membrane potential to its resting state following depolarization, typically involving the efflux of potassium ions out of the neuron.

Question 19

Hyperpolarization

Answer 19

An increase in the negative charge inside the neuron beyond its resting membrane potential, making it less likely to generate an action potential.

Question 20

Synapse

Answer 20

The junction between two neurons or between a neuron and an effector cell, where neurotransmitters are released and signal transmission occurs.

Question 21

Meninges

Answer 21

Protective membranes that surround the brain and spinal cord, providing cushioning and support.

Question 22

Ventricle

Answer 22

Fluid-filled cavities within the brain that produce and circulate cerebrospinal fluid (CSF), providing buoyancy and nourishment to the central nervous system.

Question 23

Cerebrum

Answer 23

The largest part of the brain responsible for higher cognitive functions, sensory perception, and voluntary motor control.

Question 24

Cerebellum

Answer 24

A region of the brain located beneath the cerebrum, responsible for coordinating voluntary movements, balance, and posture.

Question 25

Brain stem

Answer 25

The portion of the brain that connects the cerebrum to the spinal cord, controlling basic life functions such as breathing, heart rate, and consciousness.

Question 26

Neurotransmitter

Answer 26

Chemical messengers released by neurons at synapses to transmit signals to other neurons, muscles, or glands.

Question 27

Hormone

Answer 27

Chemical messengers secreted by endocrine glands into the bloodstream to regulate physiological processes and maintain homeostasis.