Mastering Biology Practice CH 41

To survive, all animals must _____.

balance consumption of food with use and storage of nutrients

A fat molecule also includes one, two, or three ____ molecules

fatty acid

Your small intestine can absorb ____ without their being further digested.

fructoses

A fat molecule is composed of two types of smaller molecules, including only one molecule of

glycerol

The function of mechanical digestion is to break down large chunks of food into smaller pieces. Why is this important? Smaller pieces of food _____.

have more surface area for chemical digestion than do larger pieces of food

A fatty acid includes a carboxyl group (-COOH) at one end as well as a long_____

hydrocarbon chain

What acid is responsible for stomach acidity?

hydrochloric acid

The hydrocarbon chains found in fats store a lot of energy. They also make fats ________, or insoluble in water

hydrophobic

Choose the list that presents the four stages of food processing in the order in which they naturally occur.

ingestion → digestion → absorption → elimination

Bile is produced by the _____ and stored by the _____ until it is secreted into the small intestine.

liver ... gall bladder

Starch can be broken down into the disaccharide known as _____.

maltose

a fat molecule with three fatty acids is called a triacyclglycerol, or a _____

triglyceride

Among humans, increased interest in food intake normally occurs _____.

via chemical signals released when the stomach is empty

What is the main component of gastric juice?

water

The lower esophageal sphincter surrounds the upper opening into the stomach. If this sphincter failed to properly constrict, there might be a problem with _____.

regurgitation of acidic stomach contents into the esophagus, commonly called "heartburn"

The acidity of the stomach contents triggers the small intestine to secrete a hormone known as _____.

secretin

Protein digestion begins in the _____.

stomach

Certain nutrients are considered "essential" in the diets of some animals because _____.

these animals are not able to synthesize these nutrients

_____ is secreted by the _____ and acts to emulsify _____ in the _____.

Bile ... liver ... fats ... small intestine

Choose the correct statement from the list below. Carbohydrates are fully digested after passage through the stomach . Bile salts from the gall bladder are essential to the digestion of carbohydrates. Carbohydrate digestion begins in the mouth with salivary amylase. Carbohydrate absorption occurs primarily in the large intestine.

Carbohydrate digestion begins in the mouth with salivary amylase.

Which process is not required for an animal to obtain energy from food?

Excretion

True or False? The liver is a component of the alimentary canal.

False

True or false? One advantage of having a tube-like digestive tract is that digestion of all compounds can take place simultaneously down the tract.

False

Choose the correct statement from the list below. Free fatty acid absorption occurs in the small intestine. Fats are fully digested after passage through the mouth and stomach. Bile salts from the pancreas are essential to the digestion of fats Fat digestion begins in the stomach with the activation of trypsinogen to trypsin.

Free fatty acid absorption occurs in the small intestine.

Choose the correct statement from the list below. Protein digestion begins in the small intestine with the activation of trypsinogen to trypsin The stomach has a high pH which allows for the activation of digestive enzymes. Proteins that are consumed in the diet are absorbed as individual amino acids following digestion. Mechanical digestion of proteins is more important than chemical digestion.

Proteins that are consumed in the diet are absorbed as individual amino acids following digestion.

Which structure is not part of the alimentary canal?

Salivary glands.

When digested, proteins are broken down into _____.

amino acids

Which of these enzymes begins the breakdown of starch?

amylase

When digested, fats are broken down into _____.

both glycerol and fatty acids

Different types of food are eaten by various groups of animals, but it is usually true that _____.

cellulose digestion in ruminant mammals occurs before the ingested foods reach the small intestine

The presence of fatty acids and amino acids in the chyme from the stomach triggers the small intestine to secrete a hormone known as _____.

cholecystokinin, or CCK

A fat molecule with only one fatty acid is called a _____

monoglyceride

Secretin stimulates the _____ to secrete _____.

pancreas ... bicarbonate

Cholecystokinin (CCK) stimulates the _____ to secrete _____.

pancreas ... pancreatic enzymes

Starch is a type of _____.

polysaccharide