Module 1.1 Quiz
As compared to dendrites, axons usually ____
Are covered with myelin
Glial cells ____
Are smaller but more numerous than neurons in the human brain
The branching fibers that form the information-receiving pole of the nerve cells are called ____
Dendrites
Nodes of Ranvier are _____
Gaps in the myelin of axons
Many dendrites contain short outgrowths called spines that ____
Increase the surface area available for synapses
What do neurons have that other cells do not
Large, branching extensions
Glial cells whose function most closely resembles that of the immune system are called ___
Microglia
Molecules that can cross the blood-brain barrier are usually ____
Molecules that can dissolve in the fats of the capillary walls
The two basic kinds of cells in the nervous system are ____
Neurons and glia
the stricter that contains a cell's chromosomes is called the ____
Nucleus
What type of glial cells myelinated axons in the brain and spinal cord
Oligodendrocytes
___ in the brain and spinal cord and ____ in the periphery are specialized types of glia that build the myelin sheaths that surround neurons
Oligodendrocytes; Schwann cells
Why do neurons rely so heavily on glucose as their source of nutrition
Other fuels do not readily cross the blood-brain barrier
Small, charged molecules can cross the cell membrane through ____
Protein channels
Which those of glia builds myelin sheaths around axons in the periphery of the body
Schwann cells
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 the junctions called
Synaptic receptors
Ribosomes are the part of the cell that ____
Synthesizes new proteins
What leads to Korsakoff's syndrome
Thiamine deficiency due to chronic alcoholism
The endoplasmic reticulum is a ____.
network of thin tubes that transport newly synthesized proteins
What mechanism prevents or slows some chemicals from entering the brain, while allowing others to enter
A blood-brain barrier
As a general rule, axons convey information ____
Away from their own cell body
What is the main source of nutrition for vertebrate neurons
Glucose
Chemicals are released by axons ____
Into the junction between neurons
Which type of glia remove waste material in the nervous system?
Microglia (astrocytes)
The endoplasmic reticulum is a ____
Network of thin tubes that transport newly synthesized proteins
What structure is composed of two layers of fat molecules that are free to flow around one another
The membrane
Neurons typically have one _____, but many____.
axon; dendrites
Radial glia
guide the migration of neurons and their axons and dendrites during embryonic development
Dendrites ____
Are branching fibers that get narrower near their ends
The cell membrane is composed of two layers of ____
Fat
The insulating material that covers many vertebrate axons is called the ____.
Myelin
Why does the brain need thiamine
To enable it to metabolize glucose
What type of glia helps to synchronize the activity of axons
Astrocytes
Which type of glia release chemicals that modify the activity of neighboring neurons
Astrocytes
Water, oxygen, and ____ most freely flow across a cell membrane
Carbon dioxide
If you were to accidentally touch a hot stove with your hand, you would quickly pull your hand away. The information carried to the muscles in your arm to make them contract was carried by ____
Efferent neurons
The membrane of a neuron is composed of ____ with ____ embedded in them
Fat molecules; proteins
If all of a neuron's dendrites or axons were contained within the spinal cord, it would be considered a(n) ____ neuron
Intrinsic
What type of neuron in the pons receives information only from other cells in the pons and sends information only to other cells in the pons
Intrinsic
What happens to a virus that manages to cross the blood-brain barrier and enters the brain
It remains there and may cause negative effects several years later
The major disadvantage of a blood-brain barrier is that ____.
certain required chemicals must be actively transported
Glucose enters the brain via which type of transport
Active transport
A presynaptic terminal is also known as ____
An end bulb
Korsakoff's syndrome ___
Is marked by severe memory impairments
