Introduction to the Nervous System and Neurons

These flashcards cover key concepts from the lecture on the nervous system and the structure and function of neurons.

What are the three types of muscle in the human body?

Smooth, cardiac, and skeletal muscles.

What role does nervous tissue play in muscle movement?

Nervous tissue is essential for communication between the brain and muscles, termed the neuromuscular junction.

How is skeletal muscle characterized?

Skeletal muscle is multinucleated, striated, and voluntary.

What type of neuron transmits signals from the sensory receptors to the central nervous system?

Sensory neurons.

What is the role of motor neurons?

Motor neurons transmit signals from the central nervous system to muscles and glands.

What is the soma of a neuron?

The soma is the cell body of the neuron that contains the nucleus.

What are dendrites?

Dendrites are tree-like extensions of a neuron that receive signals from other neurons.

What is the function of the myelin sheath?

The myelin sheath insulates axons, allowing for faster transmission of electrical signals.

What is an action potential?

An action potential is a rapid change in membrane potential that occurs when a neuron sends a signal.

What is the resting membrane potential of a neuron?

The resting membrane potential is typically around -70 millivolts, indicating a relatively negative internal charge.

What occurs during depolarization of a neuron?

During depolarization, sodium gates open and sodium ions rush into the neuron, making the inside more positive.

What happens during repolarization?

During repolarization, potassium gates open, potassium ions exit the neuron, making the inside more negative.

What is hyperpolarization?

Hyperpolarization occurs when the membrane potential becomes more negative than the resting potential due to excess efflux of potassium.

What is the sodium-potassium pump?

The sodium-potassium pump actively transports sodium out of the cell and potassium into the cell, using ATP.

Why is ATP important for neurons?

ATP is necessary for maintaining ion gradients via the sodium-potassium pump, which is vital for neuron function.

What is the central nervous system composed of?

The central nervous system is composed of the brain and spinal cord.

What do glial cells do?

Glial cells support and protect neurons, providing nourishment and maintaining homeostasis.