Neuroscience: Neurons and Channels

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What role do neurotransmitters play in chemically gated channels?

They open the channels when they attach to receptors. (correct)

They close the channels to prevent ion flow.

They are the ions that flow through the channels.

They are permanently bound to the channels.

What is the primary reason potassium ions move outside the cell?

There is a higher concentration of potassium inside the cell. (correct)

Potassium is repelled by negative charges inside the cell.

Potassium ions are attracted to positive charges outside the cell.

Potassium channels are permanently open, allowing continuous flow.

Which type of channel is responsive to changes in membrane potential?

Voltage-gated channels (correct)

Chemically gated channels

Leaky channels

Permanently open channels

What happens to the inside of the cell when potassium ions exit?

It becomes more negative due to a loss of positive charge. Signup and view all the answers

What is the effect of negative ions inside the cell on potassium ions?

They attract potassium ions back into the cell. Signup and view all the answers

What characterizes resting membrane potential?

There is a significant charge difference across the membrane. Signup and view all the answers

What function does the central branch of a pseudo-unipolar neuron serve?

It transmits information to the CNS. Signup and view all the answers

What is the primary function of leaky channels?

To allow passive movement of potassium ions in and out. Signup and view all the answers

What type of neuron is characterized by having one dendrite and one axon?

Bipolar neuron Signup and view all the answers

In what situation are voltage-gated channels opened?

When reaching a specific threshold of membrane potential. Signup and view all the answers

Which statement about glial cells is correct?

They can divide and form new cells. Signup and view all the answers

What is the primary characteristic of multipolar neurons?

They have many dendrites and one axon. Signup and view all the answers

Which type of neuron primarily functions in sensory information transmission?

Pseudo-unipolar neuron Signup and view all the answers

How are glial cells commonly referred to in the nervous system?

Nerve glue Signup and view all the answers

What does the peripheral branch of a pseudo-unipolar neuron do?

Picks up sensations from the skin. Signup and view all the answers

Which of the following is NOT a type of neuron mentioned?

Nullipolar neuron Signup and view all the answers

What condition is characterized by the immune system attacking myelin sheaths in the peripheral nervous system?

Multiple Sclerosis Signup and view all the answers

What is the primary role of Schwann cells in the peripheral nervous system?

Providing insulation for axons Signup and view all the answers

Which statement about unmyelinated and myelinated axons is true?

Myelinated axons transmit signals faster than unmyelinated axons. Signup and view all the answers

What impact does multiple sclerosis have on muscle function?

It leads to a loss of muscle function. Signup and view all the answers

What are the components responsible for generating resting membrane potential?

Higher concentration of potassium inside the cell Signup and view all the answers

What does 'polarized' mean in the context of neuronal function?

Having a voltage difference between two areas Signup and view all the answers

Which factor does NOT contribute to the resting membrane potential?

The active transport of calcium ions into the cell Signup and view all the answers

What symptom is NOT typically associated with multiple sclerosis?

Improved coordination Signup and view all the answers

What type of neuron is characterized by having many dendrites and one axon?

Multipolar Signup and view all the answers

Which type of glial cell is characterized by being highly branched?

Astrocytes Signup and view all the answers

What primarily distinguishes gray matter from white matter in the nervous system?

Presence of myelin sheaths Signup and view all the answers

What term is used to describe clusters of cell bodies located in the peripheral nervous system?

Ganglia Signup and view all the answers

What is the distinguishing feature of white matter?

Bundles of parallel axons with myelin sheaths Signup and view all the answers

What basic type of ion channel allows for passive movement of ions and is always open?

Leak Channel Signup and view all the answers

What causes the inside of a neuron to be more negatively charged compared to the outside?

Negatively charged proteins too large to exit Signup and view all the answers

What is the primary function of oligodendrocytes in the central nervous system?

Surround and insulate multiple axons Signup and view all the answers

What happens to reflexes below the level of spinal cord injury?

All reflexes below the injury are lost Signup and view all the answers

Which spinal nerve does not have sensory distribution to the skin?

C1 Signup and view all the answers

What does the cervical plexus primarily innervate?

Diaphragm and neck muscles Signup and view all the answers

What do spinal plexuses allow for in terms of neuron relationships?

Intermingling of neurons from different spinal nerves Signup and view all the answers

What is the clinical significance of the phrenic nerve?

It innervates the diaphragm Signup and view all the answers

What area does the brachial plexus supply nerves to?

Upper limbs and shoulder Signup and view all the answers

What is the consequence of spinal cord inflammation after trauma?

Damage to spinal cord tissue, leading to reflex loss Signup and view all the answers

How do dermatomes function in relation to the skin?

They supply sensory innervation to specific skin areas Signup and view all the answers