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Question 1

What are the two major types of cells in the nervous system?

Answer 1

Neurons and glial cells.

Question 2

What is the primary function of neurons?

Answer 2

Neurons are responsible for communication within the nervous system, using electrical and chemical signals to transmit information.

Question 3

What is the main role of glial cells in the nervous system?

Answer 3

Glial cells provide support, insulation, and protection for neurons, and they assist in maintaining homeostasis in the brain.

Question 4

What are dendrites, and what do they do?

Answer 4

Dendrites are branches of neurons that receive input from other neurons and sensory receptors.

Question 5

What is the function of the axon in a neuron?

Answer 5

The axon carries signals away from the cell body toward other neurons or effector cells.

Question 6

What is the myelin sheath, and why is it important?

Answer 6

The myelin sheath is a fatty layer covering segments of the axon that insulates the neuron and speeds up neural impulses.

Question 7

What happens at the axon terminal?

Answer 7

The axon terminal releases neurotransmitters that allow the neuron to communicate with other neurons across a synapse.

Question 8

How do neurons communicate with each other?

Answer 8

Neurons communicate using both electrical impulses (action potentials) and chemical signals (neurotransmitters).

Question 9

What are synapses?

Answer 9

Synapses are small gaps between neurons where neurotransmitters are released to transmit signals to the next neuron.

Question 10

What is neuroplasticity?

Answer 10

Neuroplasticity is the brain’s ability to reorganize and form new neural connections in response to experience or injury.

Question 11

What is the blood-brain barrier (BBB), and which cells are involved in its formation?

Answer 11

The BBB is a protective barrier that prevents harmful substances from entering the brain. Astroglial cells are involved in creating it.

Question 12

What is an action potential?

Answer 12

An action potential is a sudden, rapid increase in electrical charge that travels down a neuron’s axon when a threshold voltage is reached.

Question 13

What are astrocytes, and what function do they serve?

Answer 13

Astrocytes are glial cells that help create the blood-brain barrier and regulate blood flow in response to neuronal activity.

Question 14

What is the sodium-potassium pump, and what role does it play in neurons?

Answer 14

The sodium-potassium pump is a protein that moves sodium ions out of the neuron and potassium ions into it, helping to maintain the resting potential.

Question 15

How do glial cells contribute to the myelin sheath?

Answer 15

Oligodendroglia in the central nervous system and Schwann cells in the peripheral nervous system form the myelin sheath around axons.

Question 16

What neurotransmitter is involved in mood regulation and sleep?

Answer 16

Serotonin is involved in mood regulation, sleep, and appetite.

Question 17

What is the difference between excitatory and inhibitory neurotransmitters?

Answer 17

Excitatory neurotransmitters trigger action potentials in the postsynaptic neuron, while inhibitory neurotransmitters prevent action potentials.

Question 18

What is the role of dopamine in the brain?

Answer 18

Dopamine is involved in controlling voluntary movement, mood, and reward mechanisms.

Question 19

What is the function of GABA?

Answer 19

GABA is the main inhibitory neurotransmitter in the brain, helping to reduce neural activity and promote relaxation.

Question 20

What is neuroplasticity, and why is it important?

Answer 20

Neuroplasticity refers to the brain’s ability to change and adapt by forming new neural pathways, allowing for learning and recovery after injury.

Question 21

What is multiple sclerosis (MS), and how does it affect neurons?

Answer 21

MS is a disease that involves the degradation of the myelin sheath on neurons, leading to impaired signal transmission and symptoms like muscle weakness.

Question 22

How do action potentials travel faster along myelinated neurons?

Answer 22

Action potentials jump from one node of Ranvier (gaps in the myelin sheath) to the next, speeding up conduction through saltatory conduction.

Question 23

What is synaptic plasticity?

Answer 23

Synaptic plasticity refers to changes in the strength or number of synapses due to experience, learning, or injury, affecting how neurons communicate.

Question 24

What is acetylcholine’s role in the nervous system?

Answer 24

Acetylcholine is involved in stimulating muscles, attention, arousal, memory, and motor control.

Question 25

What happens during the refractory period of a neuron?

Answer 25

During the absolute refractory period, the neuron cannot fire another action potential, while during the relative refractory period, it can fire with a stronger-than-usual stimulus.

Question 26

What is glutamate, and what is its primary function in the brain?

Answer 26

Glutamate is the most common excitatory neurotransmitter in the brain, playing a key role in learning and memory formation.

Question 27

How do sodium and potassium ions contribute to a neuron’s resting potential?

Answer 27

Sodium ions are kept outside the neuron, while potassium ions are inside, creating a negative charge inside the neuron, which maintains the resting potential.

Question 28

What happens when neurotransmitters are released into the synaptic cleft?

Answer 28

Neurotransmitters bind to receptors on the postsynaptic neuron, causing either excitatory or inhibitory effects, depending on the type of neurotransmitter.

Question 29

What is the corpus callosum, and what is its function?

Answer 29

The corpus callosum is a bundle of axons that connects the two hemispheres of the brain, allowing communication between them.

Question 30

What is an example of brain lateralization in humans?

Answer 30

In most people, language areas such as Broca’s and Wernicke’s areas are located in the left hemisphere of the brain.

Question 31

What are interneurons, and what is their function?

Answer 31

Interneurons act as connectors, communicating between sensory and motor neurons, and also among themselves within the nervous system.

Question 32

What are sensory neurons responsible for?

Answer 32

Sensory neurons detect stimuli from the environment (such as light, sound, touch) and send this information to the brain and spinal cord.

Question 33

What do motor neurons do?

Answer 33

Motor neurons carry signals from the brain and spinal cord to muscles and glands, enabling movement and other responses.

Question 34

What is saltatory conduction?

Answer 34

Saltatory conduction is the process by which action potentials jump from one node of Ranvier to the next in myelinated neurons, speeding up signal transmission.

Question 35

What is a neurotransmitter receptor?

Answer 35

A neurotransmitter receptor is a protein on the postsynaptic neuron’s membrane that binds to neurotransmitters, enabling communication between neurons.

Question 36

What is the role of ependymal cells?

Answer 36

Ependymal cells line the brain’s ventricles and produce cerebrospinal fluid, which cushions the brain and spinal cord.

Question 37

What is hyperpolarization in a neuron?

Answer 37

Hyperpolarization is when the inside of a neuron becomes more negative than its resting potential, making it less likely for the neuron to fire an action potential.

Question 38

What is synaptic pruning?

Answer 38

Synaptic pruning is the process of eliminating weaker synaptic connections, allowing stronger and more efficient connections to thrive, which is important for brain development and plasticity.

Question 39

What is the blood-brain barrier (BBB)?

Answer 39

The BBB is a selective barrier formed by astrocytes that prevents harmful substances from entering the brain while allowing essential nutrients to pass through.

Question 40

What is the function of microglia in the nervous system?

Answer 40

Microglia act as the brain’s immune cells, cleaning up debris from dead or damaged neurons and protecting the brain from infections