ANS Spinal Reflexes Part 2 (Slides 35-42, Quiz 2)

Question 1

T/F: the neural control of the bladder involves autonomic, somatic, and cognitive circuits to inhibit or promote urination

Answer 1

true

Question 2

The sympathetic innervation from T10-L2 of the bladder travels via….

Answer 2

inferior mesenteric ganglion and pelvic plexus

Question 3

Postganglionic neurons of the bladder travel in….

Answer 3

hypogastric and pelvic nerve

Question 4

What happens when the detrusor muscle relaxes?

Answer 4

this allows the renal pelvis and bladder to fill up with urine and the internal sphincter will be closed

Question 5

Parasympathetic preganglionic neurons from S2-S4 cause ___________ of the bladder/detrusor muscle and relaxation of the internal sphincter which will cause micturition/voiding/urination

Answer 5

contraction

Question 6

The principal nerve supply of the bladder is via the ___________ nerves, which connect with the spinal cord through the sacral plexus, mainly connecting with cord segments S2 and S3

Answer 6

pelvic

Question 7

Are pelvic nerves sensory, motor, or both?

Answer 7

both

Question 8

The motor nerves transmitted in the pelvic nerves are…

Answer 8

parasympathetic fibers

Question 9

Skeletal motor fibers transmitted through the __________ n. to the external bladder sphincter

Answer 9

pudendal

Question 10

The central autonomic network regulates the balance between sympathetic and parasympathetic activity. The micturition reflex is an autonomic spinal cord reflex, but it can be inhibited or facilitated by centers in the brain. What are the 4 higher centers?

Answer 10

1) periaqueductal gray (PAG) of midbrain is responsible for emotions like when you’re stressed/upset you will pee more, same with any risks for safety or socially
2) pontine micturition center (PMC)
3) locus ceoreleus is activated by PAG
4) sensory cortex, limbic center, and emotional center

Question 11

The bladder receives _____________ innervation from the chain through the hypogastric nerves, connecting mainly with the L2 segment of the spinal cord

Answer 11

sympathetic

Question 12

What does the ANS and sexual function require?

hint: think axonal categories

Answer 12

visceral motor and somatic motor

Question 13

What happens to sexual function in a parasympathetic state?

Answer 13

-relaxes blood vessels (tunica media), which increases blood flow bc the blood vessel is dilated
-vascular dilation causes penile and clitoral erection
-stimulation of secretions
-smooth muscle contraction for ejaculation and orgasm, bulbocavernosus muscles contract rhythmically

mnemonic: point and shoot (P for parasympathetic, S for sympathetic)

Question 14

What happens to sexual function in a sympathetic state?

Answer 14

-T11-L2, chain ganglia inferior mesenteric and pelvic ganglia are working together to block arteries
-vasoconstriction= loss of erection
-sympathetic stimulation of the smooth muscle in the urethral wall causes peristalsis to help eject semen

Question 15

The sacral parasympathetic pathway controlling the sexual organs in both males and females originates in the sacral segments ________ and reaches the target organs via the pelvic nerves

Answer 15

S2-S4

Question 16

What is the ONLY postganglionic parasympathetic circuit that does not use ACh?

Answer 16

sexual function circuit

this circuit releases nitric oxide instead!!!!

Question 17

The somatic component of reflex sexual function arises from __________ neurons in the lumbar and sacral spinal cord segments. Sexual function is governed centrally by the anterior medial and medial tuberal zones of the _____________, these nuclei act as integrative centers for sexual responses

Answer 17

alpha motor, hypothalamus