Chap 18

Question 1

neural tube is developed from what?

Answer 1

brain and spinal cord

Question 2

the anterior portion of the neural tube develops into what 3 fluid filled called primary brain vesicles?

Answer 2

• prosencephalon (forbrain)
• mesencephalon (midbrain)
• rhombencephalon (hindbrain)

Question 3

the 3 primary vesicles develop into 5 secondary brain vesicles, which are

Answer 3

• telencephalon (develops the cerebrum and lateral ventricles)
• diencephalon (develops into epithalamus, thalamus, hypothalamus and 3rd ventricle)
• mesencephalon (remains unchanged and develops into midbrain and aqueduct of the midbrain)
• metencephalon (develops into pons, cerebellum and upper part of 4th ventricle)
• myelencephalon (develops into medulla oblongata and bottom part of 4th ventricle)

Question 4

the adult brain

Answer 4

85 billion neurons and 10-50 trillion neuroglia

Question 5

adult brain can be divided into what 4 major regions?

Answer 5

• brain stem (medulla oblongata, pons, and midbrain)
• cerebellum (posterior to the brain stem)
• diencephalon (superior to brain stem, consists of thalamus, hypothalamus and epithalamus)
• cerebrum (spread over diencephalon)

Question 6

brain is protected by?

Answer 6

• cranial bones
• cranial meninges (dura mater)
• middle arachnoid mater
• inner pia mater
• cerebrospinal fluid

Question 7

12 cranial nerves

Answer 7

-olfactory nerve
-optic nerve
-oculomotor nerve
-trochlear nerve
-trigeminal nerve
-abducens nerve
-facial nerve
vestibulocochlear nerve
-glossopharyngeal nerve
-vagus nerve
-accessory nerve
-hypoglossal nerve

Question 8

what are the 3 cranial nerves?

Answer 8

I, II, VIII

contains axon of sensory neurons and are called special sensory nerves

Question 9

what are the 5 cranial nerves?

Answer 9

III, IV, VI, XI, and XII

contain only axons of motor neurons and are called motor nerves

Question 10

what are the last 4 cranial nerves?

Answer 10

V, VII, IX, X

contain axon both sensory and motor neurons and are called mixed nerves