Ch. 41

Question 1

What is a Neuron?

Answer 1

A specialized cell that transmits electrical and chemical signals in the nervous system.

Question 2

What are the three main parts of a neuron?

Answer 2

The cell body, Dendrites, and axon.

Question 3

What is the function of the cell body?

Answer 3

Contains the nucleus and other organelles that help to maintain the neuron’s metabolism and other functions

Question 4

What are dendrites?

Answer 4

Are branched extensions of the cell body that receive signals from other neurons or sensory receptors.

Question 5

What is an axon?

Answer 5

A long, think extension of the cell body that transmits signals away from the cell body to other neurons or muscles.

Question 6

What is myelin?

Answer 6

A fatty substance that covers and insulated the axon of some neurons, allowing for faster signal transmission.

Question 7

What are glial cells?

Answer 7

Are non-neuronal cells in the nervous system that provide support and nourishment to neurons.

Question 8

What are the main types of glial cells?

Answer 8

Astrocytes, oligodendrocytes, microglia, and Schwann cells.

Question 9

What is the function of astrocytes?

Answer 9

Help regulate the chemical environment around neurons and provide structural support.

Question 10

What is the function of oligodendrocytes and Schwann cells?

Answer 10

Oligodendrocytes and Schwann cells produce myelin, which helps to insulate axons and increase signal transmission speed.

Question 11

What is the function of microglia?

Answer 11

Are immune cells in the nervous system that help to remove damaged cells or debris.

Question 12

What is multiple sclerosis?

Answer 12

multiple sclerosis is a neurological disorder characterized by damage to they myelin sheath, which can lead to disruptions in signal transmission and a range of symptoms.

Question 13

What is the resting membrane potential?

Answer 13

Is the electrical potential difference across the membrane of a neuron when it is at rest.

Question 14

What is the threshold potential?

Answer 14

the membrane potential at which an action potential is triggered.

Question 15

What is depolarization?

Answer 15

is a process by which the membrane potential become less negative, bring it closer to the threshold potential.

Question 16

What is the role of voltage-gated ion channels in action potentials?

Answer 16

Voltage-gated ion channels are membrane proteins that open or close in response to changes in membrane potential, allowing ions to flow in or out of the cell contribute to the generation of an action potential.

Question 17

What is the refractory period?

Answer 17

is a brief period of time after an action potential during which the neuron is temporarily unable to generate another action potential.

Question 18

What is a saltatory conduction?

Answer 18

is the process by which action potentials, jump from node to node along myelinated axons, allowing for faster signals transmission.

Question 19

What is the all-or-none principle?

Answer 19

that all-or-none principle states that an action either occurs with full strength or does not occur at all, and that the strength of an action potential is not affected by the strength of the stimulus that trigger

Question 20

What is the role of neurotransmitters in action potentials?

Answer 20

neurotransmitters are chemical messengers that are released from neurons and act on other neurons or muscles to transmit information

Question 21

What are some factors that can affect action potential generation and transmission?

Answer 21

Factors that can affect action potential generation an transmission include the diameter and myelination of axons, the presence of inhibitory or excitatory neurotransmitters, and the concentration of ions in the extracellular fluid.

Question 22

What is synapse?

Answer 22

A junction between two neurons of between a neuron and an effector cell where neural signals are transmitted.

Question 23

What is a neurotransmitter?

Answer 23

A chemical messenger released by a neuron and a effector cell where neural signals are transmitted.

Question 24

What are the two types of synapses?

Answer 24

Electrical and chemical synapses

Question 25

What happens at an electrical synapses?

Answer 25

Direct flow if electrical current between cells, allowing for rapid communication.

Question 26

What happens at a chemical synapse?

Answer 26

Neurotransmitters molecules are released from the presynaptic neuron, diffuse across the synaptic cleft, and bind to receptors on the postsynaptic neuron to transmit a signal

Question 27

What are the steps in chemical synaptic transmission?

Answer 27

1st action potential arrives at axon terminal. 2 Voltage-gated calcium channels open and calcium ions enter the presynaptic neuron. 3 Vesicles containing neurotransmitter fuse with the presynaptic membrane and release neurotransmitter into the synaptic cleft. 4 Neurotransmitter molecules bind to receptors on the postsynaptic neuron. 5 Ion channels in the postsynaptic neuron open to close, producing a response.

Question 28

What are some examples of neurotransmitters?

Answer 28

Acetylcholine, Dopamine, serotonin, norepinephrine, glutamate, GABA.

Question 29

What is reuptake?

Answer 29

The process by which neurotransmitter molecules are taken back up into the presynaptic neuron to be reused or broken.

Question 30

What is degradation?

Answer 30

The breakdown of neurotransmitter molecules by enzymes in the synaptic cleft to terminate their effects.

Question 31

What is the central nervous system?

Answer 31

The portion of the nervous system that included the brain and spinal cord.

Question 32

What are the three main functions of the central nervous system?

Answer 32

Sensory input, integration, and motor output.

Question 33

What are the three major regions of the brain?

Answer 33

The hindbrain, midbrain, and forebrain

Question 34

What are the functions of the midbrain?

Answer 34

Integrating sensory information and coordinating reflex responses.

Question 35

What are the functions of the forebrain?

Answer 35

Processing sensory information, regulating motor function, and controlling cognitive processes, such as memory and learning.

Question 36

What is the cerebral cortex?

Answer 36

The outer layer of the forebrain that is responsible for consciousness, perception, and higher cognitive functions.

Question 37

What are the four lobes of the cerebral cortex?

Answer 37

Frontal, parietal, temporal, and occipital

Question 38

What is the corpus callosum?

Answer 38

A bundle of nerve fibers that connects the two hemispheres of the cerebral cortex and allows for communication between them.

Question 39

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

Answer 39

Neurons and glial cells.

Question 40

What is the function of neurons?

Answer 40

Transmitting electrical and chemical signals throughout the nervous system.

Question 41

What is the function of glial cells?

Answer 41

Supporting and protecting neurons, as well as regulating their activity.