Chapter 14 Questions based on objectives Flashcards
What are the 4 major parts of the brain?
- Brain stem
- Cerebellum
- Diencephalon
- Cerebrum
What is the brain stem?
continuous with spinal cord and consists of medulla oblongata, pons, and midbrain.
Where is the cerebellum?
posterior to the brain stem
What is the Diencephalon, and what does it consist of?
Superior to the brain stem.
It consists of the thalamus, hypothalamus, and epithalamus.
What is the cerebrum?
the largest part of the brain. Supported by diencephalon and brain stem.
What surrounds and protects the brain?
The cranial cavity bones and the cranial meninges
The cranial meninges are continuous with the spinal meninges and consist of what 3 parts?
the outer dura mater
the middle arachnoid mater
the inner pia mater
How is the dura mater in the brain different than those of the spinal cord?
The cranial dura mater has two layers; the spinal dura mater has only one.
What are the two layers of the dura mater called?
periosteal layer (which is external) and the meningeal layer (which is internal)
Is the periosteal layer of the dura mater internal or external?
which is external
Is the meningeal layer of the dura mater internal or external?
Internal
What is the function of the dural venous sinuses (endothelial-lined venous channels)
drain venous blood from the brain and deliver it into the internal jugular veins
Blood vessels that enter brain tissue pass along the surface of the brain and do what?
They penetrate inward they are sheathed by a loose-fitting sleeve of pia mater
What are the three extensions of the dura mater that separate parts of the brain?
(1) The falx cerebri
(2) The falx cerebelli
(3) The tentorium cerebelli
How does the falx cerebri separate parts of the brain?
Separates the two hemispheres (sides) of the cerebrum.
The brain represents only ___% of the total body weight.
2%
How much oxygen and glucose are used in the brain even when at rest?
It Consumes about 20% of the oxygen and glucose used by the body, even when resting.
Blood flows to the brain mainly via the _________and vertebral_______
internal carotid
and
vertebral arteries
___________consists mainly of tight junctions that seal together the endothelial cells of brain blood capillaries and a thick basement membrane that surrounds the capillaries.
blood-brain barrier (BBB)
What is Cerebrospinal fluid (CSF)
It is a clear, colourless liquid composed primarily of water that protects the brain and spinal cord from chemical and physical injuries.
__________are cavities within the brain that are filled with cerebrospinal fluid.
Ventricles
What are the four CSF-filled cavities within the brain?
2 lateral ventricles
third ventricle
fourth ventricle
What Protects the brain from chemical and physical injuries and nourishes neurons and neuroglia
Cerebrospinal Fluid
What are the three functions of the Cerebrospinal Fluid?
- Mechanical protection
- Homeostatic function
- Circulation