Neurons/Glial/Blood brain barrier

Reticular Theory

An obsolete theory that the brain is connected to the spinal cord and all the nerves are all connected that the brain sends spirits to move muscles.

Camillo Golgi

This scientist stained neurons which made the neurons all look connected.

Santiago Ramon y Cajal

Found interest in Golgi's stain, and invented the double stain which was just staining the tissue twice which allowed for him to look at the neurons more prominently.

The neuron Doctrine

Cajal double stained juvenile animals' tissues and found that these neurons are not connected and need to send signals to each other.

Neurons

Receive and transmit information to other cells.

Dendrites

The short branch extensions on the neuron that receive information.

Cell body (Soma)

Spherical part of the neuron that contains the nucleus, ribosomes, and mitochondria; processes and integrates information.

Axon

Long extension (Like the bridge of the neuron); carries information from one end of the neuron to the other.

Presynaptic terminal

Branches and the end of the neuron; transmits information to other neurons.

Myelin Sheath

Insulating material; helps with transmission speed.

Nodes of Ranvier

Short regions on the axon that are not insulated with myelin sheath; propagates (continues to send) electrical signals.

Motor Neurons

Neurons that are used to send motor functions.

Sensory Neurons

Specialized in sensing things such as temperature.

Afferent Axon

Brings information into the body (Sensory).

Efferent Axon

Brings information out of the body (Motor).

Interneuron/intrinsic neuron

If a cells dendrites and axons are contained in a single structure (Has the shortest axon).

Action potential

When the neuron fires.

Nerve

A bundle of axons.

Astrocytes

Help synchronize the activity of axons by wrapping around neurons; they are responsible for dilating blood cells which invites more nutrients into the brain in highly active areas.

Microglia

Remove waste from the brain, as well as dead dying or damaged neurons.

Oligodendrocytes

Build the myelin sheath in the brain and spinal cord.

Schwann

Builds myelin sheath in areas of the body other than the brain and spinal cord.

Radial Glia

Is a long stick that guides the neuron to where it needs to be, depending on what the neuron will do with its specialized function.

Blood brain barrier

A mechanism that surrounds the brain and blocks most chemicals from entering the brain.

Why do we need the blood brain barrier?

Endothelial cells join so tightly that they can block almost anything from passing through to the brain which helps defend from disease and harmful things.

What happens if a virus crosses the blood brain barrier?

The microglia will step in to defend.

What viruses do cross the blood brain barrier?

Chicken pox, Rabbies, HIV, Covid (Can cross the blood brain barrier in rodents), Meningitis, Syphilis, Herpes, West nile virus; these are all viruses that cannot be cured, you have it for life.