Tag: nervous system in animals

Nodes of Ranvier are periodic gaps in the myelin sheath of medullated (myelinated) nerve fibers where the axonal membrane is exposed.

Nissl granules are composed of rough endoplasmic reticulum (RER) and free ribosomes, which are rich in RNA, giving them a strong affinity for basic dyes.

In medullated nerve fibers, the nodes of Ranvier are the specific points where the myelin sheath is interrupted and the axonal membrane comes into direct contact with the extracellular environment.

Nissl granules are essentially clusters of rough endoplasmic reticulum and ribosomes, which are the machinery responsible for protein synthesis within the neuron.

Nissl granules are characteristic cytoplasmic inclusions found specifically in the cell bodies and dendrites of nerve cells (neurons).

Nodes of Ranvier are the periodic gaps in the myelin sheath of medullated (myelinated) nerve fibers. They allow for saltatory conduction of nerve impulses.

The perikaryon (cell body) and dendrites are characteristic structures of a neuron that distinguish it from other typical animal cells. While other cells have nuclei and mitochondria, these specific extensions and the cell body structure are unique to neurons.

Schwann cells are specialized glial cells that wrap around the axons of neurons in the peripheral nervous system to form the myelin sheath.

The axon is the long projection of a neuron that is typically covered by the myelin sheath, which is a fatty insulating layer that speeds up impulse transmission.