Exam 3 Brain Lower SG (pt1) Flashcards
(24 cards)
What are the four major parts of the brain?
- Brain stem
- Cerebellum
- Diencephalon
- Cerebrum
What are the three components of the brain stem?
- Medulla oblongata
- Pons
- Midbrain
What are the two main components of the diencephalon?
Thalamus and Hypothalamus
Name the meninges of the brain in sequence from outermost to innermost
- Dura mater (outer)
- Arachnoid mater (middle)
- Pia mater (inner)
State how the cranial meninges are similar to the spinal meninges with regard to names and continuity.
cranial meninges are continuous with the spinal meninges of the same name, and have the same basic structure
What is the difference between the spinal dura mater and the cranial dura mater, regarding number of layers?
The cranial dura mater has two layers, whereas the spinal dura mater has only one
What are the names of the different layers of cranial dura mater, and from what are they derived?
- 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
Where do the layers of cranial dura mater separate?
they separate to enclose the dural venous sinuses that drain blood from the brain into the internal jugular veins
State the cranial dura mater that separates the two hemispheres of the cerebrum.
Falx cerebri
State the cranial dura mater that separates the two hemispheres of the cerebellum
Falx cerebelli
State the cranial dura mater that separates the cerebrum from the cerebellum
Tentorium cerebelli
What physiological process is used by neurons to produce ATP?
oxidative phosphorylation in mitochondria, (from glucose)
How much glucose is stored in the brain?
Virtually no glucose
What is the function of the blood-brain-barrier?
protects brain cells from harmful substances and pathogens by preventing them from entering the brain
How is the blood-brain barrier formed?
by a combination of tight junctions of the endothelial cells of brain capillaries and astrocyte foot processes
What parts of the brain lack the blood-brain barrier?
- Pineal gland
- Pituitary gland
- Hypothalamus
Describe the functions of the CSF.
- 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)
Where is CSF produced?
in the walls of the ventricles
What produces CSF?
- The choroid plexuses
- Ependymal cells, from blood plasma by filtration
What absorbs CSF?
arachnoid villi, which project into the CSF circulatory spaces
Describe the location of the first and second ventricles?
lateral ventricles together comprise them, the septum pellucidum separates them
What brain structure surrounds the third ventricle?
the right and left halves of the thalamus
Where is the fourth ventricle located?
between the brain stem and the cerebellum
How does CSF contribute to homeostasis?
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
