Section 1A

Question 0

Peristalsis is dependent on what type of contractions?

Answer 0

on involuntary contractions of smooth muscle

Question 1

Describe how Peristalsis works

Answer 1

It propels contents forward through the GI tract at varying speeds

Question 2

How does Segmentation work?

Answer 2

It promotes mechanical digestion of food. It takes large pieces of food and breaks it into smaller pieces

Question 3

How does segmentation facilitate absorption?

Answer 3

By exposing all portions of the intestinal contents to the absorbing surfaces of the GI tract

Question 4

What type of contractions is segmentation dependent on?

Answer 4

Involuntary contractions of smooth muscle

Question 5

What are the 4 types of segmentation motility?

Answer 5

Regularly spaced
Isolated
Irregularly spaced
Weak regularly spaced

Question 6

What are the two basic functions of the GI tract?

Answer 6

1. Separate food into essential nutrients and unnecessary waste
2. Absorb the essential nutrients while getting rid of the waste

Question 7

Relaxation of sphincters is mediated by what?

Answer 7

Reflexes

Question 8

Name the 6 sphincters within the Gi tract

Answer 8

Upper Esophageal Sphincter (UES)
Lower Esophageal Sphincter (LES)
Pyloric Sphincter
Ileocecal Sphincter
Internal Anal Sphincter
External Anal Sphincter

Question 9

What is the sphincter that controls movement of things Into the GI Tract?

Answer 9

Sphincter of Oddi

Question 10

What does the Sphincter of Oddi do?

Answer 10

Regulates movement of contents of the common bile duct into the duodenum

Question 11

Sphincters are dependent on what type of contractions?

Answer 11

Involuntary contractions of smooth muscle

Question 12

How do sphincters function to be a mode of motility

Answer 12

Tonic contractions of sphincters with intermittant relaxation serve to regulate movement of luminal contents

Question 13

What are the 3 basic types of motility?

Answer 13

1. Propulsive movements or PERISTALSIS
2. Mixing movements or SEGMENTATION
3. TONIC CONTRACTIONS of sphincters or valves

Question 14

What are the two things in the GI tract under voluntary control?

Answer 14

1. At the mouth through the early portion of the esophagus (including the UES), chewing muscles, swallowing, etc.
2. At the external anal sphincter (skeletal muscle)

Question 15

What three acts of the GI tract have voluntary components involving skeletal muscle?

Answer 15

1. Chewing
2. Swallowing
3. Defecation

Question 16

How much of the following is made of each per day:

Saliva, Gastric Juice, Bile, Pancreatic juice, Intestinal secretions, Mucus

Answer 16

Saliva: 1.5 L
Gastric Juice: 2.5 L
Bile: 0.5 L
Pancreatic Juice: 1.5 L
Intestinal Secretions: 1.0 L
Mucus: 2.0 L

Question 17

Define Digestion:

Answer 17

Breakdown process whereby the structurally complex foodstuffs of the diet are converted into smaller absorbable units

Question 18

What two ways can digestion occur and by what means?

Answer 18

Mechanically –> aforementioned motility

Chemically –> Enzymes

Question 19

The enzymes for chemical digestion come from where?

Answer 19

Pancreas and Stomach

Question 20

Where does digestion mainly occur?

Answer 20

In the small intestine and stomach

Question 21

Absorption solves what two problems?

Answer 21

1. How to reclaim the enormous volume of fluid (approx. 9.0 L)
2. How to recognize specific nutrients, vitamins, electrolytes and to absorb them effectively and efficiently.

Question 22

Approximately how much of the daily input of fluid ends up in stool daily?

Answer 22

100 mL

Question 23

What four mechanisms has the GI tract developed to carry out its functions?

Answer 23

1. Motility
2. Secretion
3. Digestion
4. Absorption

Question 24

Name the 4 basic quadrants

Answer 24

1. Right Upper Quadrant 2. Left Upper Quadrant 3. Right Lower Quadrant 4. Left Lower Quadrant

Question 25

Below the diaphragm, the GI organs reside in what cavity?

Answer 25

Abdominopelvic cavity

Question 26

What is the Peritoneum?

Answer 26

A slick serous membrane of the abdominopelvic cavity

Question 27

What is the visceral peritoneum?

Answer 27

It covers the external surfaces of most digestive organs and is continuous with the parietal peritoneum

Question 28

What is the parietal peritoneum?

Answer 28

It lines the walls the Abdominopelvic cavity

Question 29

T or F, Peritoneal fluid secreted by the two membranes

Answer 29

True

Question 30

What does the peritoneal fluid do?

Answer 30

The serous fluid lubricates the mobile digestive organs allowing them to glide easily across one another as they carry out their activities.

Question 31

What is peritonitis? What 3 things can cause it?

Answer 31

Inflammation of the peritoneum, may occur when one: 1) suffers a piercing wound of the abdomen 2) a perforating ulcer 3) a ruptured appendix

Question 32

What is Ascites?

Answer 32

The condition characterized by the accumulation of peritoneal fluid

Question 33

What are the peritoneal folds?

Answer 33

Located in the peritoneum. They are large folds that weave between the viscera. They are unlike pericardium and pleurae which smoothly cover the heart and lungs

Question 34

What is the example of a peritoneal fold?

Answer 34

Greater Omentum which hangs loosely from the transverse colon and small intestine.

Question 35

What is the mesentery?

Answer 35

Another example of a peritoneal fold which is found in between the small intestine and anchors it to the posterior abdominal wall.

Question 36

What are the accessory digestive organs?

Answer 36

``` Salivary glands Pancreas Biliary System (Gallbladder & Liver) ```

Question 37

Smooth muscle in GI tract walls maintain constant low level of contractions known as what?

Answer 37

Tone

Question 38

Tone is important for what 2 things?

Answer 38

1. Maintaining a steady pressure on the contents of the GI tract 2. Preventing walls from remaining permanently stretched following distention.