Physiology 🫁

Question 1

regulation of gastrointestinal function

Answer 1

Question 2

what are the types of a small intestine motility?

Answer 2

1-Segmentation contraction
2-Normal peristaltic contraction
3-Migrating motor complex (MMC)
4-peristaltic rush
5-antiperistalsis
6-Muscularis mucosa & villous contraction

Question 3

description of segmentation contraction

Answer 3

• Circular ms contract at regular intervals dividing S.I into segments then new contractions appear in middle of each segment with relaxation of previous contractions & so on..

Question 4

what is the most common type of movement of the small intestine?

Answer 4

Segmentation contraction

Question 5

what is the function of segmentation contraction?

Answer 5

Mixing movement

1- to facilitate digestion by mixing chime with juice & contact with brush border enzymes

2- to facilitate absorption

Question 6

what is the mechanism of segmentation contraction?

Answer 6

It is myogenic i.e. controlled by the basic electric rhythm (BER).

Question 7

what is the definition of basic electric rhythm (BER)?

Answer 7

It is spontaneous rhythmic fluctuation in the smooth muscles membrane potential between – 60 mv & – 40 mv.

Question 8

what initiates BER?

Answer 8

It is initiated by the interstitial cells of Cajal

Question 9

description of normal peristaltic contractions

Question 10

what is the function of normal peristaltic contractions?

Answer 10

Propulsive movement

1-propulsion of intestinal content toward colon.

2-help digestive & absorption

Question 11

mechanism of normal peristaltic contractions

Answer 11

• Neurogenic due to Local axon reflex initiated by S.I distension by chyme —-> stimulate mechano R. —-> then afferent n. to intrinsic n. plexus —–> then efferent n. to smooth ms to cause contraction before & relaxation after distended part

Question 12

what is the description of migratory motor complex?

Answer 12

• Repeated waves of peristalsis occur every 1-1.5 hours, so that when one MMC reaches the end of ileum, a new one begins in stomach. Occurs () meals, during fasting & sleep

Question 13

what is the function of migratory motor complex?

Answer 13

sweeping movement

• Help prevent upward migration of bacteria from the colo

Question 14

Description of peristalitic rush

Answer 14

strong rapid peristaltic contractions

Question 15

what is the function of Peristalitic rush?

Answer 15

evacuate the intestinal contents rapidly into the colon (leading to diarrhea).

Question 16

what is the description of antiperistalisis?

Answer 16

It is peristaltic movement in the opposite direction

Question 17

what is the function of Antiperistalisis?

Answer 17

Occurs as early event in vomiting

Question 18

what is the function of Muscularis mucosa & villous contraction?

Answer 18

cause short folds of mucosa which increase surface area for absorption

Question 19

what are the factors affecting intestinal motility?

Answer 19

Question 20

what is the apparatus used in recording intestinal Motility?

Answer 20

Power lab 4/30

Question 21

what is the solution used in power lab in Recording of intestinal motility?

Answer 21

Oxygenated tyrod solution

Question 22

what is the specimen used in power lab during the recording of untestinal motility?

Answer 22

isolated rabbit small intestine