Exam 3 Brain Lower SG (pt1)

Question 1

What are the four major parts of the brain?

Answer 1

• Brain stem
• Cerebellum
• Diencephalon
• Cerebrum

Question 2

What are the three components of the brain stem?

Answer 2

• Medulla oblongata
• Pons
• Midbrain

Question 3

What are the two main components of the diencephalon?

Answer 3

Thalamus and Hypothalamus

Question 4

Name the meninges of the brain in sequence from outermost to innermost

Answer 4

• Dura mater (outer)
• Arachnoid mater (middle)
• Pia mater (inner)

Question 5

State how the cranial meninges are similar to the spinal meninges with regard to names and continuity.

Answer 5

cranial meninges are continuous with the spinal meninges of the same name, and have the same basic structure

Question 6

What is the difference between the spinal dura mater and the cranial dura mater, regarding number of layers?

Answer 6

The cranial dura mater has two layers, whereas the spinal dura mater has only one

Question 7

What are the names of the different layers of cranial dura mater, and from what are they derived?

Answer 7

• external periosteal layer, formed by the periosteum covering the internal surface of the cranium
• internal meningeal layer, which is continuous with the dura mater covering the spinal cord

Question 8

Where do the layers of cranial dura mater separate?

Answer 8

they separate to enclose the dural venous sinuses that drain blood from the brain into the internal jugular veins

Question 9

State the cranial dura mater that separates the two hemispheres of the cerebrum.

Answer 9

Falx cerebri

Question 10

State the cranial dura mater that separates the two hemispheres of the cerebellum

Answer 10

Falx cerebelli

Question 11

State the cranial dura mater that separates the cerebrum from the cerebellum

Answer 11

Tentorium cerebelli

Question 12

What physiological process is used by neurons to produce ATP?

Answer 12

oxidative phosphorylation in mitochondria, (from glucose)

Question 13

How much glucose is stored in the brain?

Answer 13

Virtually no glucose

Question 14

What is the function of the blood-brain-barrier?

Answer 14

protects brain cells from harmful substances and pathogens by preventing them from entering the brain

Question 15

How is the blood-brain barrier formed?

Answer 15

by a combination of tight junctions of the endothelial cells of brain capillaries and astrocyte foot processes

Question 16

What parts of the brain lack the blood-brain barrier?

Answer 16

• Pineal gland
• Pituitary gland
• Hypothalamus

Question 17

Describe the functions of the CSF.

Answer 17

• Protects the brain and spinal cord against chemical and physical injuries
• Carries oxygen, glucose, and other needed chemicals from the blood to neurons and neuroglia
• Continuously circulates through cavities in the brain and spinal cord, and around the brain and spinal cord in the subarachnoid space (between the arachnoid mater and the pia mater)

Question 18

Where is CSF produced?

Answer 18

in the walls of the ventricles

Question 19

What produces CSF?

Answer 19

• The choroid plexuses

- Ependymal cells, from blood plasma by filtration

Question 20

What absorbs CSF?

Answer 20

arachnoid villi, which project into the CSF circulatory spaces

Question 21

Describe the location of the first and second ventricles?

Answer 21

lateral ventricles together comprise them, the septum pellucidum separates them

Question 22

What brain structure surrounds the third ventricle?

Answer 22

the right and left halves of the thalamus

Question 23

Where is the fourth ventricle located?

Answer 23

between the brain stem and the cerebellum

Question 24

How does CSF contribute to homeostasis?

Answer 24

Mechanical protection, protects brain and spinal cord from physical jolts

Chemical protection, provides accurate neuronal signaling

Circulation, exchange of nutrients and waste products between the blood and nervous tissue