Chapter 15: Brain and Cranial Nerves Flashcards
List the 3 major developing parts of the brain at 4 weeks of gestation.
- Prosencephalon
- Mesencephalon
- Rhombencephalon
What does the prosencephalon develop into?
- Telencephalon: cerebrum
- Diencephalon: hypothalamus, thalamus, epithalamus
What does the mesencephalon develop into?
Midbrain
What does the rhombencephalon develop into?
- Metencephalon: pons, cerebellum
- Myelencephalon: medulla oblongata
- Spinal chord
Where doe each circled regions develop from?
- Cerebrum: telencephalon
- Pons/Cerebellum: Metencephalon
- Medulla oblongata: Myelencephalon
Where do each circled regions develop from?
Pineal gland/ Thalamus/ Hypothalamus: Diencephalon
Tectal plate/ Cerebral aqueduct: Mesencephalon
The nervous tissue of the brain consists of ____ and ______.
- grey matter and white matter
Grey matter consists of neuron cell bodies, dendrites, unmyelinated axons ….
- cortex = superficial layer
- nuclei = close to surface or deep within brain
White matter consists of which three tracts?
- Association tracts
- Arcuate fibers (same lobe)
- Longitudinal fasiculi (different lobe) - Commissural tracts
- Corpus callosum (left and right hemisphere) - Projection tracts
- cerebrum to lower brain structures (cross-over)
List the 4 forms of protection and support the brain has.
- Skull (bones)
- Meninges
- Cerebrospinal fluid
- Blood-brain barrier
The three layers of connective tissue that make up the meninges are:
A. skin of scalp, periosteum, and dura mater
B. dura mater, bone of skull, and pia mater
C. dura mater, arachnoid, and pia mater
C. dura mater, arachnoid, and pia mater
What type of connective tissue is dura mater and what are it’s layers?
Dura mater (dense irregular CT)
- periosteal layer
- meningeal layer
Describe what is found in the arachnoid region.
- web of collagen and elastic fiber (trabeculae)
- subarachnoid space (CSF)
Pia mater is what kind of connective tissue and what is it “form-fitting” around?
Pia mater (areolar CT)
- fits around cerebral cortex
Label the black arrows 1-3.
- Dura mater
- Arachnoid
- Pia mater
Name the cavities and space the cerebral spinal fluid fills.
- Lateral ventricles
- Third ventricles
- Fourth ventricles
- Subarachnoid space
Match the ventricle to where they are located.
Lateral ventricle
Third ventricle
Fourth ventricle
- diencephalon
- cerebrum
- between brainstem and cerebellum
Lateral ventricle
- cerebrum
Third ventricle
- diencephalon
Fourth ventricle
- between brainstem and cerebellum
What specific supporting functions does the cerebral spinal fluid have in the brain?
- cushioning (protection)
- buoyancy
- transports nutrients and wastes
Where is CSF produced?
Choroid plexus in cavity of ventricle
CSF forms which two things that enters the ventricles of the brain?
- blood plasma
- ependymal cells
Where does CSF drain after entering the ventricle?
Arachnoid villi
The purpose of the blood-brain barrier is to prevent…?
- neuron exposure to harmful substances (drugs, wastes, fluctuating concentrations)
Which two things are separated in the blood-brain barrier?
- blood and neurons
List the 3 main components of the blood-brain barrier.
- Astrocytes
- Capillaries
- Erythrocytes in capillary