APHY102- Digestive system chapter 17

It typically takes chyme ____ hours to move through the small intestine.

3-10

What secretes a thick, alkaline mucus into the duodenum in response to stimuli?

Brunner's glands

______ from the intestinal wall stimulates the release of pancreatic juice that has a high concentration of digestive enzymes.

Cholecystokinin

What stimulates goblet cells and intestinal glands to secrete their products?

Chyme provides both mechanical and chemical stimulation.

Place the segments of the small intestine in order of which food travels.

Duodenum, Jejunum, Ileum

What is the composition of mucosa?

Epithelium, connective tissue, smooth muscle

What is the forth step of fat absorption in the small intestine?

Fats are carried off by lymph in lacteals as chylomicrons.

What is the third step of fat absorption in the small intestine?

Fats are encased in chylomicrons

What is the second step of fat absorption in the small intestine?

Fats are reconstructed into intestinal cells

What products of fat digestion are absorbed by the small intestine?

Fatty acids and glycerol

What is the first step of fat absorption in the small intestine?

Fatty acids diffuse through intestinal cells.

The mesentery that extensors from the greater curvature of the stomach and loosely hangs over the small intestine like an apron is the ______ omentum.

Greater

What does pancreatic juice do?

Has a high bicarbonate ion concentration that helps neutralize chyme and cause the intestinal contents to be alkaline

Indicate where chemical digestion of carbohydrates occurs.

In the small intestine, using enzymes secreted by pancreas and those present on the intestinal mucosa; in the mouth, using enzymes secreted in saliva.

The second and longest part of the small intestine is the ______ which delivers chyme to the last part of the small intestine called the ______.

Jejunum; Ileum

The ______ is a highly vascular organ, enclosed in a fibrous capsule, and divided into lobes.

Liver

What is the function of the liver?

Metabolize carbohydrates. lipids & proteins; stores some substances; removes toxic substances from the blood; and secretes bile

What are the functions of motor movements in the alimentary canal?

Move the contents along the tract; mix the contents with fluids.

peptidase

Mucosal cells; breaks down peptides into amino acids

What stimulates the secretion of large volume of watery saliva?

Parasympathetic impulses

What factors enhance movements in small intestines?

Parasympathetic stimulation dissension of the stomach wall dissension of the duodenal wall

The mesentery is a double-layered extension of the ______, and is attached to the small intestine.

Peritoneum

pancreas

Produces and secretes pancreatic juice, containing digestive enzymes and bicarbonate ions, into small intestine

liver

Produces bile, which emulsifies fat

stomach

Secretes acid and enzymes. Mixes food with secretions to begin enzymatic digestion of proteins

______ from the duodenum stimulates the release of pancreatic juice that contains few digestive enzymes but has a high bicarbonate ion concentration.

Secretin

What is the lumen?

The opening in the digestive tract that food passes through

cephalic phase

The sight, taste, smell, or thought of food triggers parasympathetic reflexes. Gastric juice is secreted in response.

What function do the circular folds, villi, and microvilli lining the small intestine have in common?

They increase the surface area for maximum nutrient absorption.

Name the microscopic fingerlike projections of the small intestine lining that increase the surface area, allowing increased absorption.

Villi

double contrast barium enema

X-ray exam following ingestion of contrast agent highlights blockage in large intestine

pepsin

a protein-splitting enzyme that digests nearly all types of dietary protein into polypeptides; formed from pepsinogen in the presence of hydrochloric acid

What is the function of the large intestine?

absorbs water and electrolytes and forms and stores feces

large intestine

absorbs water and forms feces

Peptidases are enzymes that split peptides into what smaller molecules?

amino acids

What is a peptidase?

an enzyme that digests protein.

intestinal phase

as food enters the small intestine, it stimulates intestinal cells to release intestinal gastrin, which, in turn, briefly promotes the secretion of gastric juice from the stomach wall. this phase primarily inhibits gastric juice secretion

colon is divided into

ascending, transverse, descending, sigmoid

Where are the lingual tonsils located?

base of tongue

What does bile contain?

bile salts, bile pigments, cholesterol, electrolytes

fecal occult blood test

blood detected in feces sample

teeth

break food particles into smaller pieces; help mix food with saliva during chewing

Digestion of ______ begins in the mouth with the activity of salivary amylase and is completed in the small intestine by enzymes from the intestinal mucosa and pancreas

carbohydrates

What is the stomach divided into?

cardia, fundus, body, & pylorus

What does the large intestine consist of?

cecum, colon, rectum, anal canal

The condition in which the autoimmune response to eating gluten damages and destroys microvilli in the small intestine called ______ disease.

celiac

What are the three phases of gastric secretion?

cephalic, gastric, intestinal

pharynx

connects mouth to esophagus

lips

contain sensory receptors used to judge characteristics of foods

Protein metabolism in liver

dominates amino acids; forms urea; synthesizes plasma proteins; converts certain amino acids into other amino acids

Where are the palatine tonsils located?

either side of the tongue in the back of the mouth

Sigmoidoscopy and colonoscopy

endoscope views rectum and lower colon

Pancreatic juice contains

enzymes that digest carbohydrates, fats, proteins, nucleic acids

What is the composition of serosa?

epithelium, connective tissue

The ______ passes through the mediastinum and penetrates the diaphragm.

esophagus

gastric phase

food in stomach chemically and mechanically stimulates release of gastrin, which, in turn, stimulates secretion of gastric juices; reflex responses also stimulate gastric juice secretion

What are the stages of swallowing?

food mixes with salvia and forced into pharynx; involuntary reflex actions move the food into the esophagus; peristalsis transports food in the esophagus to the stomach

gastric lipase

gastric glands; begins butterfat digestion

pepsin

gastric glands; begins protein digestion

What hormone enhances gastric secretion?

gastrin

The tubular glands within the mucosa and submucosa of the small intestine are called intestinal ______.

glands

cheeks

hold food in mouth; muscles chew food

palate

holds food in mouth; directs food to pharynx

What controls movement of the intestinal contents from the small intestine into the large intestine?

ileocecal sphincter

As the food leaves the ______, it enters the large intestine.

ileum

pepsinogen

inactive form of pepsin; chief cells of the gastric glands

The sympathetic nervous system _______ propelling and mixing movements in the GI tract, which is the ______ effect by the parasympathetic nervous system

inhibits; opposite

What structures secrete a large amount of watery fluid that has a nearly neutral pit and is devoid of enzymes?

intestinal glands

What is the small intestine functions?

it receives secretion from the pancreas and liver, completes digestion of nutrients, absorbs the products of digestion and transports the residues to the large intestine.

Lactose intolerance involves a lack of functioning ______, an enzyme that degrades lactose.

lactase

The enzyme ______ digests lactose into glucose and galactose

lactase

A lymphatic capillary within the core of an intestinal villus, necessary for the absorption of lipids, is called a(n) ______.

lacteal

Describe the parotid salivary glands?

largest and secrete saliva rich in amylase

A chylomicron is a ______ droplet surrounded by ______.

lipid; protein

VLDL molecules transport triglycerides from the ______ to cells of the body. Once the triglyceride has been removed they are converted into ______ molecules.

liver; LDL

Describe the submandibular salivary gland

located in the floor of the mouth, produce viscus salvia containing amylase

Describe the sublingual salivary gland

located on the floor of the mouth, primary secrete mucus.

What is the jejunum?

longest part of the small intestine

What is the composition of submucosa?

loose connective tissue, blood vessels, lymphatic vessels, nerves

The ______ ______ ______, at the end of the esophagus, help prevent regurgitation of food from the stomach.

lower esophageal sphincter

mouth

mechanical breakdown of food; begins chemical digestion of carbohydrates

Intestinal digestive enzymes are embedded in the membranes of the ______, microscopic projections on a cell wall.

microvilli

What is the brush border?

microvilli from epithelial cells lining the small intestine

Which structures increase the surface area in the small intestine lining?

microvilli; circular folds; villi

small intestine

mixes food with bile and pancreatic juice; final enzymatic breakdown of food molecules; main site of nutrient absorption

tongue

mixes food with saliva; moves food toward pharynx; contains taste receptors

The movements of the small intestine include segmentation which ______ intestinal contents and peristaltic contracts which ______ intestinal contents.

mixes; propels

What product of carbohydrates digestion gets absorbed into the blood stream by the small intestine?

monosaccharides

What are the functions of the tongue?

move food toward the pharynx during swallowing; mix food with saliva during chewing

What is the function of muscularis?

movements of the tube and its contents

What are the four layers of the structure of the wall of the alimentary canal?

mucosa, submucosa, muscular, serosa

sucrase, maltase, lactase

mucosal cells; breaks down disaccharides into monosaccharides

intestinal lipase

mucosal cells; breaks down fats into fatty acids and glycerol

Enterokinase

mucosal cells; converts trypsinogen into trypsin

Salivary glands including mucous cells secrete what?

mucus

colorectal cancer gene test

mutations associated with colorectal cancer detected in DNA of cells shed with feces

What are the structures of the pharynx?

nasopharynx, oropharynx, laryngopharynx

intrinsic factor

necessary for vitamin b12 absorption in the small intestines; parietal cells of the gastric glands

What is the function of submucosa?

nourishes surrounding tissues, transports absorbed materials

What is the main function of the small intestine?

nutrient absorption

In the digestive system, water is absorbed through the process of ______, following the absorption of salts and organic nutrients.

osmosis

lipid metabolism in liver

oxidizes fatty acids, synthesizes lipoproteins, phospholipids and cholesterol, converts excess portions of carbohydrates molecules into fat molecules

The ______ is closely associated with the duodenum.

pancreas

nucleases

pancreas; break down nucleic acids into nucleotides

pancreatic lipase

pancreas; breaks down fats into fatty acids and glycerol

carboxypeptidase

pancreas; breaks down peptides into amino acids

trypsin, chymotrypsin

pancreas; breaks down proteins or partially digested proteins into peptides

pancreatic amylase

pancreas; breaks down starch and glycogen into disaccharides

The wavelike set of muscular contractions within the digestive tract that helps to propel contents along is called ________?

peristalsis

esophagus

peristalsis pushes food to stomach

Diarrhea is the result of a ______ in the small intestine that pushes all the contents, and water, into the large intestine.

peristaltic rush

digital rectal exam

physician palpates large intestine and rectum

carbohydrate metabolism in liver

polymerizes glucose to glycogen; breaks down glycogen to glucose; converts noncarbohydrates to glucose

secretion in liver

products and secretes bile

What is the function of serosa?

protection and lubrication

What is the function of mucosa?

protection, secretion, absorption

mucus

provides a viscous, alkaline protective layer on the stomach's inner surface; mucous cells

hydrochloric acid

provides the acid environment needed for protection and action of pepsin; parietal cells of the gastric glands

Bile pigments are products of ______ breakdown

red blood cell

rectum

regulates elimination of feces

blood filtering in liver

removes damaged red blood cells and foreign substances by phagocytosis

Detoxification in liver

removes toxins from the blood

Where is the liver located?

right upper quadrant

Salivary glands including serous cells secrete what?

salivary amylase

salivary amylase

salivary glands; begins carbohydrate digestion by breaking down starch and glycogen to disaccharides

What do the salivary glands do?

secrete saliva

salivary glands

secrete saliva, which contains enzymes that initiate breakdown of carbohydrates

The type of movement in the small intestine that is alternately contracting and relaxing of muscles that results in mixing the contents is called __________?

segmentation

In the small intestine, normal mixing movements are called ______ and normal propelling movements are ______.

segmentation; peristalsis

The ______ _____ extends from the pyloric sphincter to the large intestine.

small intestine

The byproduct of protein digestion gets absorbed into the blood stream in the ______ by the process of ______.

small intestine; active transport

What is the composition of muscularis?

smooth muscle cells in circular and longitudinal groups

The prefix "gastro" means

stomach

Chemical digestion of proteins begins in the ______ as a result of ______ activity, and is completed in the small intestine by enzymes from the intestinal mucous and the ______.

stomach; pepsin; pancreas

gallbladder

stores and concentrates bile and releases it into small intestine

What does the gallbladder do?

stores bile between meals

storage in liver

stores glycogen, vitamins A, D, and B12, iron and blood

The ______ plexus in the GI tract controls secretions and the _______ plexus is important in controlling GI motility.

submucosal; myenteric

The enzyme ______ digests sucrose into glucose and fructose.

sucrase

Where is the small intestines located?

suspended from the posterior abdominal wall from mesentery

What is mastication?

the act of chewing

What is digestion?

the process of mechanically and chemically breaking down food so they can be absorbed.

The parasympathetic nervous system controls digestive functions and alters the activity of the digestive system via the ______ nerve

valgus

many bacteria inhabit the large intestine, where they breakdown what undigestible substances?

vitamin K, vitamin B12, thiamine, and riboflavin