HESI Digestive System

HESI Hint

During mastication, the teeth reduce ingested food material to smaller particles to increase surface area for chemical digestion. Collectively, a bowl of ping-pong balls has far more surface area than a basketball, just as applesauce present more surface area than a whole apple. The muscular movements of the stomach and intestines also result in mechanical breakdown of food, thus increasing surface area for digestion.

_________ are absorbed through the walls of the small intestine.

Nutrients

Intestinal Flora

abundant bacteria in the large intestne

Saliva contains an enzyme called

analyse

The large intestine is arranged into 5 portions:

ascending colon, transverse colon, descending colon, sigmoid colon, and rectum

Bolus is a

ball of food

Amino acids and simple sugars derived from proteins and carbohydrates are absorbed directly into the _______.

blood

Mastication is also known as

chewing

The stomach muscle churns and mixes the bolus of food, turning the mass into a soupy substance called _______.

chyme

Analyse is an enzyme that starts the digestion of _______ __________.

complex carbohydrates

_________ and _________ of food occurs in the small intestine.

digestion absorption

The alimentary canal is also known as the

digestive tube

The small intestine consist of three major regions:

duodenum, jejunum, ileum

In the small intestine, food is acted on by ________ from the small intestine and pancreas and by ______ from the liver.

enzymes bile

The ______ is a narrow tube leading from the pharynx to the stomach.

esophagus

The stomach stores ______ and regulates the movement of it into the __________.

food small intestine

The digestive tract has ____ main layers.

four

Food enters the stomach where _____ glands secrete ________ acid that breaks down foods.

gastric hydrochloric

All nutrients enter the ______ portal vein to be routed to the liver for ___________.

hepatic decontamination

Mastication is the process of

ingesting food into the mouth where it is mechanically broken down by the teeth and tongue.

The _____________ reabsorbs water and stores and eliminates undigested food.

large intestine

The accessory organs of digestion include

liver, pancreas, and gallbladder

Saliva _______ and dilutes the chewed food.

lubricates

Most of the fats are absorbed into the _____ by the _______. And are eventually added to the bloodstream.

lymph lacteals

The alimentary canal or digestive tube consists of the

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

main layers of digestive tract (innermost to outermost)

mucous membrane, submucous layer, muscular layer, serous layer

The ________ also contributes water to dilute the chyme and bicarbonate ions to neutralize the acid from the stomach.

pancreas

Constrictive muscles of the _______ force the food into the upper portion of the esophagus, and the food is swallowed.

pharynx

Saliva is produced by _______ pairs of salivary glands.

three

_______ are small finger-like projections that greatly increase the surface area of the intestinal wall.

Villi