A&P2 Chapter 26 - Digestive System

Which are tunics (layers) that make up the gastrointestinal wall? Check all that apply.

(Adventia)serosa muscularis mucosa submucosa

Two sets of teeth develop and erupt; the first set are 20 teeth called deciduous (milk) teeth and the final set are ____ teeth called permanent teeth.

32

Which phase(s) of gastric secretion is (are) regulated by the medulla oblongata?

All three phases are regulated by the medulla oblongata

Which of the following is not secreted by the stomach to aid in digestion?

Bile

A portal triad consists of which three structures?

Branches of a hepatic artery, hepatic portal vein, and bile ductule

What is the function of bile?

Break down fats to assist in their chemical digestion

As material moves through the large intestine, in what order does it pass through these structures?

Cecum Ascending colon Transverse colon Left colic flexure Descending colon Sigmoid flexure Rectum Anal canal

What are the three phases of gastric secretion?

Cephalic, gastric, and intestinal

Intestinal glands

Contain enteroendocrine cells

Bile from the liver and digestive juices from the pancreas enter which section of the small intestine?

Duodenum

Bolus passes from esophagus to stomach.

Esophageal phase

Peristalsis moves food bolus onward The lower esophageal sphincter relaxes

Esophageal phase

Carbohydrate digestion begins in the stomach.

False

Gastric secretion is increased in all three phases (cephalic, gastric, intestinal).

False

Mastication is the process of chemically reducing food bulk into smaller particles to facilitate swallowing.

False

Protein digestion begins in the small intestine.

False

The epithelial lining of the oral cavity has a transitional epithelium.

False

The esophagus extends from the nasopharynx to the stomach. The esophagus is about 25 meters long. The esophagus lies anterior to the trachea.

False

The liver lobule is the same as a hepatocyte.

False

The liver stores, concentrates, and releases bile into the duodenum.

False

The muscularis of the GI tract contains two layers of smooth muscles: the outer circular layer and the inner longitudinal layer.

False

When chyme enters the duodenum, gastric secretion increases.

False

When substances are moved through the epithelial cells that line the GI tract wall and are carried into the blood or lymph, this process is called secretion.

False

G-cells of the gastric glands in the stomach produce a hormone called __________ that stimulates stomach secretions and motility.

Gastrin

What are the primary hormones that participate in the regulation of the processes of digestion? Check all that apply.

Gastrin Cholecystokinin (CCK) Secretin

Parietal cells of the gastric glands in the stomach produce

HCl (hydrochloric acid)

What are the names of anatomic structures in the oral cavity? Check all that apply.

Hard plate Uvula

Normal bacterial flora in the large intestine are responsible for the production of vitamins B and

K

Which of the following is the correct order for the major parts of the gastrointestinal tract?

Mouth, esophagus, stomach, small intestine, large intestine

Check all that are a function of the esophagus.

Movement of a bolus of food from the pharynx to the stomach Prevents materials from returning from the stomach

Which of the following enzymes is produced by the stomach?

Pepsin

Select all that are major functions of the muscularis layer of the GI tract.

Peristalsis Mixing

Bolus passes from pharynx to esophagus.

Pharyngeal phase

Initiated by stimulation of tactile receptors in the oropharynx Begins with elevation of the soft palate The upper esophageal sphincter relaxes

Pharyngeal phase

Which of the following does not stimulate the secretion of HCl in the stomach?

Secretin

From external to internal, what is the correct order of layers of the stomach?

Serosa, muscularis, submucosa, mucosa

Circular folds

Slow passage of material

Secretin and cholecystokinin (CCK) are hormones that are secreted from what GI organ?

Small intestine

Check all that are characteristics of the esophagus.

The mucosa is composed of thick, nonkeratinized stratified squamous epithelium. The two layers of muscle in the superior one-third of the muscularis are skeletal

Which two fetal remnants are found on the liver?

The round ligament and the ligamentum venosum

Defecation reflexes are stimulated by the presence of feces in the rectum.

True

Gastrin functions to increase the production of HCl in the stomach.

True

Mass movements of the colon propel its contents toward the rectum.

True

Stimulation of the salivary glands is primarily through parasympathetic neurons from the facial (VII) cranial nerve to the submandibular and sublingual glands and from the glossopharyngeal (IX) cranial nerve to the parotid gland.

True

The duodenum is considered part of the upper gastrointestinal (GI) tract.

True

The muscularis of the esophagus is different from other parts of the digestive tract because the superior part of the esophagus consists of skeletal muscle. The esophagus contains both an upper and a lower esophageal sphincter that regulates the movement of materials into and out of the esophagus. The esophagus contains numerous mucous glands that produce a thick, lubricating mucus that coats the inner surface of the esophagus.

True

Chewing forms a bolus.

Voluntary phase

Food bolus forced into the oropharynx Food bolus pushed by tongue against the hard palate

Voluntary phase

The process of moving substances through the epithelial cells that line the GI tract into the blood or lymph is called

absorption

Salivary __________ breaks the chemical bond between two glucose molecules; it breaks down the long polysaccharide starch molecule into smaller and smaller pieces until only glucose results

amylase

Which region of the stomach is continuous with the esophagus?

cardiac region

Motility and secretion in the stomach is generated by the __________ reflex initiated by thought, smell, sight, or taste of food.

cephalic

Functions of the stomach include

chemical and mechanical digestion

Which cell of the gastric glands produces pepsinogen?

chief cells

The intestinal phase of digestion involves both the intestinal reflex and the release of two primary hormones: _______ and secretin.

cholecystokinin (CCK)

Which of the following are considered small intestine brush border enzymes participating in carbohydrate digestion?

dextrinase lactase sucrase

Receives bile and pancreatic juice

duodenum

Mass movements of the colon are integrated by

enteric plexus

Mass movements in the colon are stimulated by

food in the stomach and chyme in the duodenum

Structurally, the human liver is divided into how many lobes?

four

The greater omentum extends inferiorly like an apron from the _________ of the stomach and covers most of the abdominal organs.

greater curvature

Secretin is released from the duodenum in response to

hydrochloric acid in chyme

Controls entry of material into large intestine

ileum

Performs most chemical digestion and absorption

jejunum

The muscularis mucosae is a thin layer of smooth muscle immediately deep (external) to the

lamina propria of the mucosa.

The stomach is located in which abdominal quadrant?

left upper

Gastric secretion during the intestinal phase is inhibited by the presence of

lipids or low pH

What organ produces bile?

liver

Chewing requires the coordinated activities of teeth, skeletal muscles in lips, tongue, cheeks, and jaws that are controlled by nuclei within the medulla oblongata and pons, collectively called the ____________ center.

mastication

What are the names of the individual mesenteries associated with specific GI organs? Check all that apply.

mesocolon greater omentum faliciform ligament

Digested triglycerides are contained within the _____________ prior to being transported across the simple columnar epithelial lining of the small intestine into the epithelial cells.

micelles

Digestion begins in the

mouth

The mucosa of the esophagus is lined with ___________ squamous epithelium.

nonkeratinized stratified

DNA and RNA (nucleic acids) are polymers of nucleotides that are broken down, first, by pancreatic enzymes and then completed by intestinal brush border enzymes which include phosphatase and _____________.

nucleosidase

The _________ is a mixed gland with endocrine and exocrine functions that produces the majority of the digestive enzymes.

pancreas

The accessory organs of the lower GI tract include the liver, gallbladder, and

pancreas

Which of these are accessory organs of the GI tract? Check all that apply.

pancreas, gallbladder

The majority of triglyceride digestion occurs in the small intestine facilitated by the enzyme

pancreatic lipase.

Defecation is stimulated by

parasympathetic and local reflexes

Smooth muscle activity in the small intestine wall facilitates chemical digestion and absorption employing the processes of segmentation and

peristalsis.

The process of moving a bolus through the GI tract as a result of involuntary muscle contractions is referred to as

peristalsis.

Between the partietal and visceral peritoneum is the thin

peritoneal cavity.

Which organs and accessory structures are considered part of the upper GI tract? Check all that apply.

pharynx duodenum stomach esophagus

Which of the following is not a function of the digestive system?

production of ATP

Which of the following regions of the large intestine is a muscular tube that expands to store accumulated material prior to defecation, and terminates at the anal canal?

rectum

Which of the following structures are anatomically part of each tooth? Check all that apply.

root pulp enamel

Submucosal glands

secrete alkaline mucous

Enteroendocrine cells

secrete digestive hormones

Basic functions of the liver include

secretion, storage, and detoxification

Digestive reflexes that do not involve the central nervous system but instead are local and occur only within the enteric nervous system are called ________ reflexes

short

Most GI tract organs are lined with a ________ epithelium.

simple columnar

The stomach is lined by a

simple columnar epithelium

Check all that line the mucosa of the large intestine.

simple columnar epithelium globlet cells intestinal glands

During digestion, the major site of nutrient absorption is the

small intestine

Most nutrient absorption occurs in the

small intestine

The muscularis usually contains two layers of _____ muscle.

smooth

Hydrochloric acid is secreted in the

stomach

Which of these is an organ of the gastrointestinal tract as opposed to an accessory organ?

stomach

Which of the following might stimulate the cephalic phase of gastric secretion?

the thought of food

What are the serous membranes of the GI tract called? Check all that apply.

visceral peritoneum parietal peritoneum