Brain: Overview & Protective Layers

Question 1

Main 4 main regions of the brain and their functions

Answer 1

BRAIN STEM
- necessary for survival, integrated reflexes
CEREBELLUM
- judges locomotion, balance, posture
DIENCEPHALON
- nervous system connection to endocrine system
- thalamus, epithalamus, hypothalamus, subthalamous
CEREBRUM (largest part)
- higher order function, conscious thought, control

Question 2

Components of the brainstem (inferior to superior)

Answer 2

• Medulla Oblongata
• Pons
• Midbrain

Question 3

where are the 4 main regions of the brain located in relation to each other?

Answer 3

brain stem most inferior
diencephalon superior to brain stem (like a cap)
cerebellum posterior to brain stem
cerebrum is the largest structure, the steryotypical brain structure

Question 4

main protective structure of the brain

Answer 4

• cranial bones
• cranial menignes (pia, arachnoid, dura mater)
• cerebrospinal fluid

Question 5

name the 3 mininges layers superficial to deep

Answer 5

Dura matter
- periosteal dura (stuck to bone)
- miningeal dura
Arachnoid matter
Pia matter

Question 6

dural venous sinuses

Answer 6

dural because gaps in dura:
gaps between periosteal dura and miningeal dura matter
venous sinuses:
carrying venous blood

Question 7

features and function of dura matter

Answer 7

• periosteal dura (stuck to bone)
• miningeal dura
  gap between these creates dural venous sinuses

Question 8

features and function of arachnoid matter

Answer 8

• thin layer of fiberous membrane
• web like structure

Question 9

features and function of pia matter

Answer 9

• thin membrane that closely adheres to cerebrum, follows every groove, extends down spinal cors

Question 10

name spaces beteween mininges

Answer 10

Between dura and arachnoid: SUBDURAL SPACE
- contains small amount of serous fluid
Between arachnoid and pia: SUBARACHNOID SPACE
- contains cerebral spinal fluid

Question 11

What creates cerebral spinal fluid?

Answer 11

spaces in brain
VENTRICLES

Question 12

anatomy of the ventricles (brain)

Answer 12

LATERAL VENTRICLES
- 2 c-shaped spaces in brain, either side of corpus callosum
- anterior, posterior and inferior HORNS
THIRD VENTRICLE
- inbetween lateral ventricles
- INTERVENTRICULAR FORAMEN connects lateral ventricles to third ventricle
- CEREBRAL AQUADUCT runs through midbrain, ends at…
FOURTH VENTRICLE
- leads to central canal of spinal cord
- has 4 openings that CSF can exit through to subarachnoid space

Question 13

what cells create cerebrospinal fluid

Answer 13

epindymal cells

Question 14

What is CFS made of and what is it used for

Answer 14

cerebral spinal fluid
- serum-like, lacking proteins, but contains nutrients
- bathes and protects spinal cord
- most synthesized in CHOROID PLEXUS

Question 15

What is a choroid plexus

Answer 15

specialized ependymal cells that help make CSF
- layer of connective tissue attactched to capillaries in ventricles
- covered in ependyman cells that create tight junctions to filter blood into CSF

Question 16

CFS flow

Answer 16

• created in choroid plexuses of lateral venricles
• interventricular foramen
• third ventricle
• cerebral aqueduct
• fourth ventricle
• 2 lateral and 1 median aperture
• subarachnoid space
• arachnoid vili of dural venous sinuses
• venous blood
• heart and lungs
  venous blood then circulatess back to choroid plexuses of the ventricles