Definitions

Question 1

Neuron

Answer 1

The fundamental unit of the nervous system, responsible for transmitting electrical and chemical signals.

Question 2

Dendrite

Answer 2

Branched structures on a neuron that receive signals from other neurons.

Question 3

Axon

Answer 3

A long projection of a neuron that transmits electrical impulses away from the cell body.

Question 4

Myelin Sheath

Answer 4

A fatty layer surrounding axons that increases the speed of nerve signal conduction.

Question 5

Action Potential

Answer 5

A rapid electrical signal that travels along an axon, resulting from ion exchange across the membrane.

Question 6

Resting Membrane Potential

Answer 6

The electrical charge difference across the neuronal membrane when the neuron is not active (typically -70 mV).

Question 7

Central Nervous System (CNS)

Answer 7

The brain and spinal cord, responsible for processing and integrating information.

Question 8

Peripheral Nervous System (PNS)

Answer 8

Nervous system components outside the CNS, including sensory and motor neurons.

Question 9

Cerebral Cortex

Answer 9

The outer layer of the cerebrum, involved in higher-order functions such as decision-making, language, and perception.

Question 10

Hippocampus

Answer 10

A brain region involved in memory formation and spatial navigation.

Question 11

Amygdala

Answer 11

Part of the limbic system, responsible for processing emotions such as fear and aggression.

Question 12

Thalamus

Answer 12

A relay center in the brain that processes and transmits sensory and motor signals to the cerebral cortex.

Question 13

Basal Ganglia

Answer 13

A group of subcortical structures involved in motor control and reward processing.

Question 14

Synapse

Answer 14

The junction between two neurons where chemical or electrical signals are transmitted.

Question 15

Neurotransmitter

Answer 15

A chemical released at the synapse to transmit signals between neurons (e.g., dopamine, serotonin, glutamate).

Question 16

Depolarization

Answer 16

A decrease in membrane potential, making the interior of the cell less negative.

Question 17

Repolarization

Answer 17

The return of the membrane potential to a negative value after depolarization.

Question 18

Hyperpolarization

Answer 18

An increase in membrane potential, making the interior of the cell more negative.

Question 19

Excitatory Postsynaptic Potential (EPSP)

Answer 19

A change in membrane potential that increases the likelihood of an action potential.

Question 20

Inhibitory Postsynaptic Potential (IPSP)

Answer 20

A change in membrane potential that decreases the likelihood of an action potential.

Question 21

Dopamine

Answer 21

A neurotransmitter involved in reward, motivation, and motor control.

Question 22

Serotonin (5-HT)

Answer 22

Regulates mood, appetite, and sleep; targeted by SSRIs in depression treatment.

Question 23

Acetylcholine

Answer 23

Important for muscle contraction, learning, and memory.

Question 24

Glutamate

Answer 24

The primary excitatory neurotransmitter in the CNS.

Question 25

GABA (Gamma-Aminobutyric Acid)

Answer 25

The main inhibitory neurotransmitter in the CNS.

Question 26

Astrocyte

Answer 26

A type of glial cell that provides support, regulates blood flow, and maintains the blood-brain barrier.

Question 27

Microglia

Answer 27

Immune cells of the CNS that remove debris and protect against pathogens.

Question 28

Oligodendrocyte

Answer 28

A glial cell in the CNS that forms myelin.

Question 29

Schwann Cell

Answer 29

A glial cell in the PNS that forms myelin.

Question 30

Node of Ranvier

Answer 30

Gaps in the myelin sheath where action potentials are regenerated.

Question 31

Somatosensory System

Answer 31

Processes sensory information such as touch, temperature, and pain.

Question 32

Motor Cortex

Answer 32

The brain region responsible for planning and executing voluntary movements.

Question 33

Reflex Arc

Answer 33

A neural pathway that mediates an automatic response to a stimulus.

Question 34

Parkinson’s Disease

Answer 34

A disorder characterized by motor deficits caused by the degeneration of dopaminergic neurons in the substantia nigra.

Question 35

Alzheimer’s Disease

Answer 35

A neurodegenerative condition involving memory loss, often associated with amyloid plaques and neurofibrillary tangles.

Question 36

Multiple Sclerosis (MS)

Answer 36

An autoimmune disorder where the immune system attacks the myelin sheath, disrupting neural transmission.