PSYC 233 Final Exam

Glial cells ____.​

Are smaller but more numerous than neurons in the human brain.

What type of glia helps to synchronize the activity of axons?​

Astrocytes

The membrane of a neuron is composed of ____ with ____ embedded in them.​

Fat molecules; proteins

What is the main source of nutrition for vertebrate neurons?​

Glucose

Chemicals are released by axons ____.​

Into the junction between the neurons

Glial cells whose function most closely resembles that of the immune system are called ____.​

Microglia

The structure that contains a cell's chromosomes is called the ____.​

Nucleus

An axon has many branches, each of which swells at its tip. These are known as ____.​

Presynaptic terminals

Neurons differ most strongly from other body cells in their ____.​

Shape

The surface of a dendrite is lined with specialized junctions through which the dendrite receives information from other neurons. What are these junctions called?​

Synaptic receptors

What mechanism prevents or slows some chemicals from entering the brain, while allowing others to enter?​

A blood-brain barrier

Which type of glia remove waste material in the nervous system?​

Astrocytes

The major disadvantage of a blood-brain barrier is that ____.​

Certain required chemicals must be actively transported

The cell membrane is composed of two layers of _____.​

Fat

Radial glia ____.​

Guide the migration of neurons during embryonic development

Many dendrites contain short outgrowths called spines that _____.​

Increase the surface area available for synapses

The insulating material that covers many vertebrate axons is called the ____.​

Myelin sheath

Why does the brain need thiamine?​

To enable it to metabolize glucose

Molecules that can cross the blood-brain barrier are usually ____.​

molecules that can dissolve in the fats of the capillary walls

Why do neurons rely so heavily on glucose as their source of nutrition?​

​Other fuels do not readily cross the blood-brain barrier.