Cells
IN THE NERVOUS SYSTEM
What is a nerve cell?
Cells of the nervous system, called nerve cells or neurons, are specialized to carry "messages" throughout our body. The human brain has approximately 100 billion neurons. Neurons come in many different shapes and sizes. Some of the smallest neurons have cell bodies that are only 4 microns wide. Some of the biggest neurons have cell bodies that are 100 microns wide. To understand how small that is, divide 1 mm by 1000 and that is how big a micron is.
What are the important parts of a nerve cell?
Dendrite: Bring electrical signals (messages) to the cell from the brain.
Axon: Take electrical signals (messages) away from the cell.
Nucleus: The control center of a cell, containing that cells genetic material.
Synapse: The place where chemical signals can be sent to other cells. Essentially, it is what allows the cell to "speak" by translating electrical information.
Cell body: The largest part of a cell, holding the nucleus, which is the control center for the cell. The cell body also contains many other unique structures responsible for making energy and getting rid of cellular wastes.
Axon: Take electrical signals (messages) away from the cell.
Nucleus: The control center of a cell, containing that cells genetic material.
Synapse: The place where chemical signals can be sent to other cells. Essentially, it is what allows the cell to "speak" by translating electrical information.
Cell body: The largest part of a cell, holding the nucleus, which is the control center for the cell. The cell body also contains many other unique structures responsible for making energy and getting rid of cellular wastes.
what are the different types of nerve cells?
Sensory Neurons: Send information from sensory receptors (e.g., in skin, eyes, nose, tongue, ears). They move towards the central nervous system.
Motor Neurons: Send information to muscles and glands. They move away from the central nervous system.
Interneurons: Send information between sensory neurons and motor neurons. They are located directly in the central nervous system.