Lab 9: Nervous System I

Question 1

List the layers of the meninges in order from most superficial to most deep

Answer 1

1) Dura mater
2) Arachnoid mater
3) Pia mater

Question 2

The empty space between the pia and arachnoid mater is called what?

Answer 2

The subarachnoid space

Question 3

What is the function of the subarachnoid space?

Answer 3

To circulate CSF (cerebrospinal fluid)

Question 4

Name the 4 plexuses and where they’re located

Answer 4

1) Cervical: C1-5
2) Brachial: C5-T1
3) Lumbar: L1-4
4) Sacral: L4-S4

Question 5

What nerve is a part of the cervical plexus?

Answer 5

Phrenic nerve

Question 6

What 4 nerves are a part of the brachial plexus?

Answer 6

Axillary
Radial
Median
Ulnar

Question 7

What 2 nerves are a part of the lumbar plexus?

Answer 7

Femoral and obturator

Question 8

What 2 nerves are a part of the sacral plexus?

Answer 8

Sciatic and pudenal

Question 9

What muscle does the phrenic nerve act on, and what does that muscle do?

Answer 9

The diaphragm, the contraction of which causes inhalation

Question 10

What 2 muscles are innervated by the axillary nerve, and what do they do?

Answer 10

1) Deltoid: abduction of the arm

2) Teres minor: rotates the humerus laterally

Question 11

What nerve is known to be very short?

Answer 11

The axillary nerve

Question 12

What nerve is located on the posterior arm?

Answer 12

The radial nerve

Question 13

What nerve is located on the middle of the forearm?

Answer 13

Median nerve

Question 14

What 5 muscles are innervated by the radial nerve, and what do they do?

Answer 14

1) Triceps brachii: extension of the forearm
2-5) Extensor carpi radialis brevis, extensor carpi radialis lungs, extensor carpi ulnaris, and extensor digitorum: extension of the wrist

Question 15

What 4 muscles are innervated by the median nerve, and what do they do? (hint: one muscle serves 2 functions)

Answer 15

1-3) Flexor carpi radialis, palmaris longus, and flexor digitorum: flexion of the wrist

3) Flexor digitorum: flexion of the fingers
4) Pronator teres: pronation

Question 16

What muscle is innervated by the ulnar nerve, and what does it do?

Answer 16

Flexor carpi ulnaris: flexion of the wrist

Question 17

What 5 muscles are innervated by the femoral nerve, and what do they do? (hint: one muscle has 2 functions)

Answer 17

1-4) Vastus lateralis, vastus medius, vastus intermedius, and rectus femoris: extension of the knee

4) Rectus femoris: flexion of the hip
5) Sartorius: flexus, abducts, and laterally rotates the hip

Question 18

What 3 muscles are innervated by the obturator nerve, and what is their function?

Answer 18

Gracilis, adductor longus, and adductor magnus: adduction of the hip

Question 19

What nerve travels the anterior thigh?

Answer 19

Femoral nerve

Question 20

What nerve innervates only adductors?

Answer 20

Obturator nerve

Question 21

What nerve travels down the posterior thigh?

Answer 21

Sciatic nerve

Question 22

What nerve is best described as short and located in the pelvis?

Answer 22

Pudenal nerve

Question 23

What 3 muscles are innervated by the sciatic nerve, and what are their functions?

Answer 23

Biceps femoris, semitendinosus, and semimembranosus: extension of the hip and flexion of the knee

Question 24

What 2 muscles are innervated by the pudenal nerve, and what do they do?

Answer 24

1) External urethral sphincter: voluntary control of urination
2) External anal sphincter: voluntary control of defecation

Question 25

What plexuses innervate the torso and above?

Answer 25

Cervical and brachial