The tubelike digestive system canal that extends from the mouth to the anus is known as the__________canal or the _________tract?

Alimentary canal or gastrointestinal tract

Differentiate between the colon and the large intestine?

Large intestine extends from the ileocecal valve to the anus. Colon is part of the large intestine and is divided into ascending, descending, and Transverse (sigmoid) colon.

What is the role of the gallbladder?

Stores bile

Why is the liver so dark red in the living animal?

High amount of blood that circulates through the liver

What is the function of Kupffer cells of the liver?

Sinusoid walls; remove debris such as bacteria or won-out blood cells from the blood.

List the three characteristics of enzymes?

specificity
temperature specific
pH specific

Waves of muscular contractions that propel the contents of the digestive tract from one point to another are called?

Peristalsis

The esophagus is a part of the ______, while the pancreas is considered a(n) _______ when it comes to the digestive system?

alimentary canal... accessory digestive organ

The correct sequence for the layers in the walls of the alimentary canal from innermost to outermost is the…?

mucosa, submucosa, muscle layer, serosa

1. The majority of absorption occurs in the ________?

small intestine

List the four layers of the wall of the alimentary canal in the appropriate order from innermost to outermost?

mucosa, submucosa, muscularis externa and serosa

List accessory organs of digestive system?

Teeth, tongue, gallbladder, salivary glands, liver, pancreas

The _________ are double layers of peritoneum that extend from the body wall to the digestive viscera and help anchor them in place?

mesenteries

List functions of the stomach?

Storage, mechanical breakdown, disruption of chemical bonds, production of intrinsic factor

Which organ is responsible for dehydration and compaction of indigestible materials?

large intestine

What is the function(s) of HCl (hydrochloric acid)?

Kill most bacteria, denature proteins, inactivate food enzymes, breakdown plant cells and connective tissue in meat, activate pepsinogen to pepsin

Where are the motor neurons that control smooth muscle contraction and glandular secretions of the GI tract located?

Myenteric Plexus

Chemical digestion is initiated in the _________?

mouth

Why does your mouth suddenly “go dry” when you are about to deliver a presentation to a large crowd?

sympathetic activity inhibits salivation

List functions of digestive system?

Releasing nutrients from food, and absorbing those nutrients

List functions of saliva?

-provide lubrication

-help to control bacterial populations in the mouth

-bind food together àmoistening

-begin chemical digestion of carbohydrates

-enzyme salivary amylase breaks polysaccharides into disaccharides

What is a possible side effect of weakening of the cardiac sphincter?

acid reflux into the esophagus

The stomach is able to expand nearly 100 times its empty volume partly due to _________ in its walls?

rugae

A patient with a low RBC count receives vitamin B12 injections every 2 weeks. Why injection not orally?

parietal cells in this patient's stomach have ceased producing intrinsic factor

Why is pepsin inactive when tested at pH 7?

pepsin's activity is specific to the stomach's pH of 1.5-3.5

Digestion of which of the following (proteins, carbohydrate, fats) might be inhibited if a patient chronically consumes an antacid?

protein

When your stomach growls in response to an ad on TV for food, the _________ phase of gastric secretion is initiated?

cephalic

The parietal cells of gastric glands secrete?

Hydrochloric acid

The ______ cells are responsible for HCl production?

parietal

What is the primary stimulus for intestinal gland secretion of secretin?

an acidic content

distension of the intestinal wall

What is the primary stimulus for intestinal gland secretion of Cholecystokinin (CCK)?

fats.

______ stimulates the gallbladder to contract?

CCK

Salivary amylase digests…?

Starch

Cirrhosis of the liver would most severely impact digestion of _________? why?

lipids

In terms of absorption, the large intestine’s greatest contribution is?

absorption of water.

List organs of alimentary canal from mouth to anus?

mouth, pharynx, esophagus, stomach, small intestine, large intestine, and anus.

Gastric pit are?

Pockets in the lining of the stomach that contain secretory cells

Propulsion of food along the digestive tract is achieved by wave like muscle contraction called?

Peristalsis

Pockets in the lining of the stomach that contain secretory cells are…?

Gastric pits

Peristalsis is?

Waves of muscular contractions that propel the contents of the digestive tract from one point to another

Which histological layer of the alimentary canal is also known as the visceral peritoneum?

Serosa

The membrane that lines the body wall of the abdominal cavity is the?

parietal peritoneum.

Saliva is composed mainly of…….?

water

The prominent ridges in the lining of the empty stomach are called?

rugae

An intestinal hormone that stimulates the gall bladder to release bile is?

choleceystokinin

An intestinal hormone that stimulates the pancreas to release bicarbonate is?

secretin

The gastric cells that secrete pepsinogen are the….?

Chief cells

Most of the digestive enzymes found in the small intestine are secreted by which accessory organ of digestive system?

Pancreas

Parietal cells of stomach secrete?

secrete hydrochloric acid (HCl) and intrinsic factor

The pylorus empties into the?

duodenum

Why absorption cannot occur in stomach?

Food is too large and need to be small. Need to be broken down to its monomers.

The fingerlike projections of the intestinal mucosa are called?

villi

Which region of the stomach does the esophagus connect to?

cardia

Which substance secreted by the pancreas helps neutralize chyme?

Bicarbonate

Which hormone triggers the release of enzyme-rich pancreatic juice and constriction of gall bladder to eject bile?

Cck hormone

Mary had her stomach mostly removed to try to overcome obesity. As a result you would expect Mary to be at risk for _________ . Why?

pernicious anemia

G cells of the stomach secrete?

gastrin.

List functions of large intestine?

-secretion = mucus

-absorption = water and electrolytes

-storage = feces

Openings into gastric glands are called?

Gastric Pit

Gastric pits are?

Openings into gastric glands

The activities of the digestive system are regulated by?

intrinsic nerve plexuses.
parasympathetic and sympathetic neurons.
hormones.
the contents of the digestive tract.

Amylase allows us to digest?

Carbohydrates

Micelles are formed during the absorption of which nutrient?

Fatty acids (Fats)

The portion of the small intestine that is attached to the pylorus of the stomach is the…?

Duodenum

Intrinsic factor is produced in the stomach and is necessary for the absorption of?

Vitamin B12

List functions of mesenteries?

Stabilizes the organs, provide pathway for bloodvessels and lymphathic vessels, prevent your intestine from being twisted or tangled

Which age-related changes in the digestive system are the results of decreased smooth muscle tone?

Weaker peristaltic contractions and decrease in motility.
Presence of Hemorrhoids and esophageal reflux.

Chief cells of stomach secrete?

Zymogen-pepsinogen, a precursor to pepsin

The four major layers of the GI tract are ______?

Mucosa, Submucosa, Muscularis Externa, Serosa/Adventitia

The major histological differences between the large intestine and small intestine are that the large intestine ______?

Lacks villi, has abundant goblet cells, and deeper intestinal glands.

How do most chylomicrons enter the lymphatic system?

Through Lacteals

All of the enzymes that digest protein are secreted in an …. Form? Why?

secreted in an inactive form.

Where in the human body will chemical digestion begin?

In the Oral Cavity

Where are the motor neurons that control smooth muscle contraction and glandular secretions of the GI tract located?

In the Myenteric Plexus

Heartburn is usually caused by the effects of gastric juice on the?

esophagus

The portion of stomach that connects to the esophagus is the….?

Cardia

The portion of stomach that connects to the duodenum …..?

pylorus

How do the roles of pepsinogen and HCI interact in the stomach?

HCl is necessary for the conversion of pepsinogen to pepsin.

Secretion of cholecystokinin from the intestinal wall is stimulated by?

protein and fat in the small intestine.

What effect(s) does the secretion of CCK have on a fatty meal’s entrance to the duodenum?

Inhibits secretion of gastric acids and enzymes, slowing gastric emptying

The myenteric plexus is….?

The myenteric plexus, otherwise known as Auerbach's plexus, is the poriton of the enteric nervous system located between the outer longitudinal and inner circular smooth muscle layers of the wall of the GI tract

How many pairs of salivary gland are there in human oral cavity?

3 pairs

The alimentary canal extends, in its entirety, from the …. to the……?

1. mouth
2. anus

The enzymes of the digestive system are classified as hydrolases. What does this mean?

hydrolyses break down organic food molecules by adding water to the molecular bonds, thus cleaving the bonds between the subunits or monomers

Fill in the following chart about the various digestive system enzymes?

Assume you have been chewing a piece of bread for 5 or 6 minutes. How would you expect its taste to change during this interval?

the bread would begin to taste sweet because starch is broken down to glucose by amylase.

Gallstones are usually composed of?

Cholesterol

Using a flowchart, trace the pathway of a chicken sandwich (chicken = protein and fat; bread = starch) from the mouth to the site of absorption of its breakdown products, noting where digestion occurs and what specific enzymes are involved and what are the end products at that site.

Name the end products of digestion for the following types of foods

Polymer (product before digestion) Monomer or the end product after digestion

Proteins

Carbohydrates

Fats

Various types of glands form a part of the alimentary tube wall and release their secretions into it. Match the glands or their product listed in the key to the appropriate description bellow.

Key: salivary glands, gall bladder, liver, pancreas, duodenal glands, Chief cells , gastric glands, HCl (hydrochloric acid)

a. produce(s) mucus; found in the submucosa of the small intestine?

b. produce(s) a product containing amylase that begins starch breakdown in the mouth?

c. stores and modifies bile?

d. produce(s) a whole spectrum of enzymes and an alkaline fluid that is secreted into the duodenum?

e. converts pepsingogen to pepsin?

f. produce(s) bile that it secretes into the duodenum via the bile duct?

g. produce(s) HCl and pepsinogen?

h. produces enzyme that initiates digestion of protein in the stomach?

1. duodenal glands
2. salivary glands
3. Gall bladder
4. pancreas
5. HCl
6. liver
7. gastric glands
8. Chief Cells

Bile salts function like detergents in that they ___________ fat globules?

emulsify

List the correct sequence for the digestion of lipids?

Immunsafide by the bile then -> hydrolyzed

The roof of the oral cavity is formed by the?

Soft and hard pallet

Functions of the tongue include?

-mechcanical processing (mixing food)

-manipulation to assist chewing and swallowing

-sensory analysis

-secretion of mucus and enzyme (lingual lipase)

Some of the digestive organs have groups of secretory cells that release hormones into the blood.

These hormones exert an effect on the digestive process by acting on other cells, glands or structures and causing them to release digestive enzymes, cause contraction to eject bile, or increase the motility of the digestive tract. For each hormone below, note the organ producing the hormone and its effects on the digestive process. Include the target organs affected.

Hormone Produced by Target organ(s) and effects

Secretin

Gastrin

Cholecystokinin

(CCK)

Use the following keys to match them with appropriate definitions bellow:

Key: villi, tongue,
mesentery, oral cavity, stomach, esophagus, pharynx, microvilli, rugae, ileocecal valve, anus,
small intestine, pyloric valve, large intestine, stomach

1. structure that suspends the small intestine from the posterior body wall?
2. folds that allow stomach to stretch?
3. fingerlike extensions of the intestinal mucosa that increase the surface area for absorption?
4. regions that break down foodstuffs mechanically?
5. mobile organ that manipulates food in the mouth and initiates swallowing?
6. conduit for both air and food?
7. the “gullet”; no digestive/absorptive function?
8. folds of the gastric mucosa?
9. valve at the junction of the small and large intestines
10. projections of the plasma membrane of a mucosal epithelial cell?
11. absorbs water and forms feces?
12. primary region of food absorption?
13. initiates protein digestion?
14. valve controlling food movement from the stomach into the duodenum?
15. principal site for the synthesis of vitamin K by microorganisms?
16. region containing two sphincters through which feces are expelled from the body?

1. Mesentery
2. d
3. Villi
4. oral cavity, stomach
5. Tongue
6. pharynx
7. esophagus
8. rugae
9. ileocecal valve
10. microvilli
11. large intestine
12. small intestine
13. stomach
14. pyloric valve
15. large intestine
16. anus

use the diagram bellow to answer the following questions:

1. What is the function of the structure labeled "6"?
2. Identify the stomach region labeled "12"?
3. Which structure helps the stomach to stretch as it fills with food?
4. Identify the structure labeled "7”?

1. Pyloric Sphincter
   1. Regulates Passageway into the duodenum
2. Fundus
3. d
4. Pylorus