Cells of the Nervous System and Neuron Function

These flashcards provide an overview of key concepts related to the cells of the nervous system and their functions, focusing on neurons, glia, action potentials, and related biological processes.

What are the two main types of cells that make up the nervous system?

Neurons and Glia.

Who shared the 1906 Nobel Prize for their discoveries related to the nervous system?

Ramón Cajal and Camillo Golgi.

How many neurons are estimated to be in the human brain?

Approximately 86 billion neurons.

What are the main components of a neuron?

A soma (cell body), dendrites, an axon, and presynaptic terminals.

What is the role of dendrites in a neuron?

They receive information from other neurons.

What transforms energy from the environment into electrical energy in sensory receptors?

Receptors.

What is the diameter of a typical neuron membrane?

About 8 nanometers thick.

What is the resting potential of a neuron?

Typically around -70 millivolts (mV).

What does the sodium-potassium pump do?

It transports 3 sodium ions out of the cell and 2 potassium ions into the cell.

What is an action potential?

A massive depolarization of the membrane that allows neurons to transmit information.

What mechanism allows action potentials to travel faster along myelinated axons?

Saltatory conduction.

What is the composition of myelin sheaths?

A lipid-rich material composed of fats and proteins.

What phenomenon occurs when one excited neuron reduces the activity of nearby neurons?

Lateral inhibition.

What are afferent and efferent neurons?

Afferent neurons bring information into a structure; efferent neurons carry information away from a structure.

What is a ganglion cell?

A neuron in the retina that receives inputs from other retinal cells.

What is the significance of the nodes of Ranvier?

They are interruptions in the myelin sheath that facilitate the jumping of action potentials.