Ch.3 Nutrition Hw pt 1

Peristalsis

Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system.

Once a bolus becomes chyme it is ready to

enter the duodenum.

The ________ prevents chyme from exiting the stomach too soon and blocks the intestinal contents from returning to the stomach.he

pyloric sphincter

The pyloric sphincter is located between

stomach and duodenum

The fingerlike projections which line the small intestine increase the surface area to maximize absorption and help mix the partially digested chyme with intestinal secretions are

villi.

The large intestine absorbs

water

As fat enters the duodenum, the gallbladder

contracts, secreting a greenish fluid called bile, which emulsifies the fat, breaking it into smaller particles.

The process of excreting or removing undigested and unabsorbed food components from the body is called

elimination

The gallbladder secretes bile, which

emulsifies the fat, breaking it into smaller particles.

The LES contracts to prevent stomach contents from returning to the

esophagus.

The ________ receives bile from the liver through the common hepatic duct.

gallbladder

A muscle located at the end of the esophagus must relax before the bolus can enter the stomach. This muscle is called the

gastroesophageal or lower esophageal sphincter

Digestion, absorption, and elimination occur in the

gastrointestinal tract.

The breakdown of food via enzymatic reactions is known as __________.

chemical digestion

enzymes pepsin and gastric lipase

chemically digest proteins and fats

The semiliquid mass that leaves the stomach and enters the small intestine is called

chyme

Pepsin can begin the digestion of protein in the stomach after it is converted from pepsinogen by __________.

HCl

Food that has been moistened with saliva and then swallowed through the esophagus is called

a bolus

The process of moving nutrients from the GI tract into the circulatory system.

absorption

The villi and microvilli are the site of nutrient

absorption.

As the trachea closes, the esophagus

allowing the bolus to be swallowed into the esophagus

The enzyme in saliva is salivary __________, which begins to digest carbohydrates.

amylase

The soft palate also rises to seal off the nasal passages to prevent

aspiration of food or liquid into the sinuses.

The stomach secretes gastric juices containing

hydrochloric acid (HCL) and the enzymes pepsin and gastric lipase

As the waste material enters the cecum, it mixes with

intestinal bacteria, which digest any remaining particles.

Mechanical digestion in the stomach mixes and churns the bolus until

it becomes a liquid called chyme.

The lowest portion of the GI tract, where water and electrolytes are absorbed and waste is eliminated, is the

large intestine

Undigested or unabsorbed nutrients and other compounds from food enter the

large intestine through the ileocecal valve.

The sequence of food processing in the gut is

mastication, digestion, absorption, excretion.

Without properly functioning sphincters, the food mass would

move in the wrong direction

chemical digestion

occurs when enzymes break apart large molecules into smaller molecules

The forward, rhythmic motion that moves food through the digestive system is called

peristalsis

The presence of chyme in the duodenum stimulates the gallbladder and the pancreas to

release bile and pancreatic juice.

Most nutrient absorption takes place in the __________.

small intestine

Chyme is the semiliquid, partially digested food mass that leaves the stomach and enters the

small intestine.

The duodenum, jejunum, and ileum represent the

small intestine.

The bolus moves to the back of the mouth, and the brain temporarily closes

the epiglottis to prevent the bolus from entering the trachea.

As the bolus nears the end of the esophagus, a muscle called the gastroesophageal or lower esophageal sphincter relaxes to allow

the food into the stomach.

The presence of chyme in the duodenum stimulates two important accessory organs

the gallbladder and the pancreas

Enzymes released in saliva in the mouth start

the process of chemical digestion.