CH 1.1 Summary Flashcards
Neurons receive information and convey it to other cells.
The nervous system also contains glia, cells that enhance and modify the activity of neurons in many ways.
In the late 1800s, Santiago Ramón y Cajal used newly discovered staining techniques to establish that
The nervous system is composed of separate cells, now known as neurons.
Neurons contain the same internal structures as
Other animal cells.
Neurons have these major parts
A cell body (or soma), dendrites, an axon with branches, and presynaptic terminals.
Neurons’ shapes vary greatly depending on
Their functions and their connections with other cells.
Because of the blood–brain barrier, many molecules cannot enter the brain.
The barrier protects the nervous system from viruses and many dangerous chemicals.
The blood–brain barrier consists of an unbroken wall of cells that
Surround the blood vessels of the brain and spinal cord.
A few small, uncharged molecules such as water, oxygen, and carbon dioxide cross the barrier freely.
So do molecules that dissolve in fats.
Active transport proteins pump
Glucose, amino acids into the brain and spinal cord.
Certain hormones, including insulin, also cross the blood–brain barrier.
Neurons rely heavily on glucose, the only nutrient that crosses the blood–brain barrier in large quantities.
They need thiamine (vitamin ) to use glucose.
