Brain Lab

Question 1

What is cerebrospinal fluid?

Answer 1

clear liquid composed of water, oxygen, glucose, chemicals (blood, neurons, neuroglia)

Question 2

What are the 4 CSF cavities within the brain called?

Answer 2

• Lateral ventricle (one in each hemisphere)
• Third ventricle
• Fourth ventricle

Question 3

Where is CSF found?

Answer 3

In the subarachnoid space around the brain and spinal cord

Question 4

What are the functions of CSF?

Answer 4

1. Mechanical - shock absorbing
2. Homeostatic - pH of CSF affects ventilation + cerebral blood flow
3. Circulatory - minor exchange of nutrients and waste

Question 5

Where does CSF formation take place?

Answer 5

In the choroid plexuses, which are networks of capillaries in the walls of the ventricles.

Primarily, CSF formation takes place in the lateral ventricles

Question 6

What are fenestrated capillaries?

Answer 6

‘Leaky’ capillaries (surrounded by holes)

Question 7

where does CSF flow?

Answer 7

Choroid plexus lining the lateral ventricles produces CSF, which goes through the interventricular foramen to the 3rd ventricle.

Choroid plexus lining the 3rd ventricle produces CSF, which accumulates with the CSF flowing from lateral ventricles and combined CSF flows through the cerebral aqueduct to the 4th ventricle.

Choroid plexus lining the 4th ventricle produces CSF, which accumulates with the CSF flowing from the 3rd ventricle and combined CSF flows through the lateral and median apertures to the subdural space

The CSF flows in the subdural space around the brain and spinal cord.

CSF is reabsorbed through arachnoid villi.

Question 8

What are the three extensions of the dura mater in the brain?

Answer 8

1. The falx cerebri
2. The falx cerebelli
3. The tentorium cerebelli

Question 9

What does the falx cerebri do?

Answer 9

separates the 2 hemispheres of the cerebrum

Question 10

What does the falx cerebelli do?

Answer 10

separates the 2 hemispheres of the cerebellum

Question 11

What does the tentorium cerebelli do?

Answer 11

separates the cerebrum from the cerebellum

Question 12

What are the white matter tracts?

Answer 12

1. association fibres - run between the same hemispheres (e.g. arcuate fasciculus)
2. commisural fibres - run between hemispheres (e.g. corpus callosum)
3. projection fibre - connects lower areas to cortex (e.g. afferent and efferent)