Nervous System - AP Biology (2024)

they jump from the middle of the gaps to the middle of the myelin sheaths

additional impulses boost their speed periodically

they speed up dramatically in areas with more myelin wrapping, depending on the thickness of the sheath

they jump from gap to gap in between the myelin sheaths

Correct answer:

they jump from gap to gap in between the myelin sheaths

Explanation:

The tiny gaps in between myelin sheaths are referred to as nodes of Ranvier. The action potential will jump from node to node as it moves down the axon.

If an axon existed without these gaps (the entire length was covered in myelin), it would be unable to conduct an action potential.

Dendrites

Synaptic terminal

Soma

Axon

Correct answer:

Dendrites

Explanation:

Neurotransmitters from presynaptic cells are received by the dendrites of postsynaptic cells. There are myriad dendrites on each neuron that then propagate this signal to the soma (or cell body), allowing the signal to be passed down the axon to another neuron.

The axon is the site of neurotransmitter production

The axon contains the cell nucleus

There are often numerous axons for each neuron

The axon carries action potentials away from the cell body of a neuron

Correct answer:

The axon carries action potentials away from the cell body of a neuron

Explanation:

The axon carries action potentials away from the cell body of a neuron via a sequence of continuous depolarization. The cell body, or soma, however, is the site of neurotransmitter production and the location of the nucleus and other organelles. Every single neuron contains only one axon.

Schwann cells only

Oligodendrocytes only

Schwann cells and oligodendrocytes

Correct answer:

Schwann cells and oligodendrocytes

Explanation:

Schwann cells produce myelin for neurons of the peripheral nervous system, while oligodendrocytes produce myelin for neurons of the central nervous system.

Dendrite, axon, synaptic terminal,cell body

Dendrite, synaptic terminal, cell body, axon

Dendrite, axon,cell body, synaptic terminal

Synaptic terminal, dendrite, cell body, axon

Dendrite, cell body, axon, synaptic terminal

Correct answer:

Dendrite, cell body, axon, synaptic terminal

Explanation:

A neuron receives input from other neurons at the dendrites. Neurotransmitters released by other neurons bind to receptors on the dendrites, which carry the signal to the cell body. The signal is then amplified in the cell body before being transferred to the axon. Once the signal transitions to the axon, it is considered an action potential. The signal eventually reaches the end of the axon, where the synaptic vesicles are located, and stimulates release of neurotransmitters to the next neuron's dendrites.

Neurons contain multiple dendrites and cell bodies

The propagation of signal through a neuron initiates at the dendrite, enters the cell body, and is transmitted from the axon

Neurons transmit electrical signals from one cell to the other at the cell body

If an electrical disturbance is large enough in the cell body, the signal generates an action potential at the dendrite

Correct answer:

The propagation of signal through a neuron initiates at the dendrite, enters the cell body, and is transmitted from the axon

Explanation:

Neurons have many dendrites, one cell body, and a single axon with several terminal branches. A dendrite receives an external stimulus and causes an electrical disturbance in the cell body. This electrical disturbance is transmitted to the axon, where an action potential is generated if the stimulus is large enough. The action potential is propagated through the axon and is transmitted to a neighboring neuron at the synapse.

A large enough electrical disturbance will generate an action potential in the axon, but no magnitude of stimulus can create an action potential in the dendrites. Neurons do contain multiple dendrites, but they only contain one cell body and one axon. Finally, neurons transmit electrical signals to other neurons at the synapse, not at the cell body.

gap junctions

tight junctions

anchoring junctions

desmosomes

Correct answer:

gap junctions

Explanation:

There are two types of synapses: chemical and electrical. Chemical synapses use chemical signals called neurotransmitters to transmit nerve signals between neurons, whereas electrical synapses use electrical signals. These electrical signals are transmitted through a gap junction that connects adjacent neurons. Intercalated discs in cardiac muscle contain gap junctions for the purpose of propagating electrical signals to cause systole.

Astrocytes

Microglia

Schwann cells

Oligodendrocytes

Ependymal cells

Correct answer:

Schwann cells

Explanation:

While both oligodendrocytes and Schwann cells produce myelin sheaths that insulate nervous system signals, only the Schwann cells are found in the peripheral nervous system.

All other cells listed are found only in the central nervous system. Microglia act as immune cells within the cerebrospinal fluid, since lymphocytes are barred entry by the blood-brain barrier. Astrocytes support the neural cells and provide nutrients. Ependymal cells are responsible for secreting cerebrospinal fluid.

Glial cells

Myocytes

Ependymal cells

Schwann cells

Astrocytes

Correct answer:

Schwann cells

Explanation:

The correct answer is Schwann cells. Schwann cells are cells that produce the myelination present on the outer covering of the axon of the neuron. This lipid-rich material helps facilitate the movement of the action potential along the axon from the axon hillock to the axon terminal branches.

nephrons

neurotransmitters

neurons

Correct answer:

neurons

Explanation:

Neurons are the functional unit of the nervous system. Dendrites of the neuron accept incoming action potentials and stimuli, and propagate the signal down the cell axon to stimulate other nearby neurons.

Nephrons are the functional unit of the kidney. Gray matter refers to the regions in the central nervous system where the axonal cell bodies are located, while white matter refers to the regions that contain axons. Neurotransmitters are the particles used to transmit signals across synapses from one neuron to another.