bio chapter 41

When digested, proteins are broken down into _____.

amino acids

When digested, fats are broken down into _____.

both glycerol and fatty acids

Starch is a type of _____.


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


Which of these enzymes begins the breakdown of starch?


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


Protein digestion begins in the _____.


What is the main component of gastric juice?


What acid is responsible for stomach acidity?

hydrochloric acid

The gastrovascular cavity differs from the alimentary canal in that only the gastrovascular cavity _____.

has only a single opening

Which organ converts fructose to fat?



food being taken in, taken apart, and taken up

essential nutrients

preassembled organic molecules and minerals; materials that an animal cannot assemble from simple organic molecules

essential amino acids

amino acids required by animals that must be obtained from food in prefabricated form

essential fatty acids

fatty acids required by animals that must be obtained from food


organic molecules that are required in the diet in small amounts


inorganic nutrients, like iron and sulfur, that are required in small amounts


diet that lacks essential nutrients or consistently supplies less chemical energy than the body requires

golden rice

strain of rice that synthesizes pigment beta caroten to vitamin A


diet that fails to provide adequate sources of chemical energy

4 stages of food digestion

1. ingestion
2. digestion
3. absorption
4. elimination


the act of eating or feeding


food is broken down into molecules small enough for the body to absorb


the animal cells take up small molecules like amino acids and simple sugars


undigested material passes out of the digestive system

chemical digestion

enzymatic hydrolysis

extracellular digestion

breakdown of food particles outside the cell

gastrovascular cavity

functions in digestion as well as in distribution of nutrients throughout the body

alimentary canal

a complete digestive tract that allows animals to ingest food while earlier meals are still being digested

4 feeding mechanisms of animals

1. filter feeding
2. substrate feeding
3. fluid feeding
4. bulk feeding

filter feeders

strain small organisms/ food from the surrounding medium (aquatic animals)

substrate feeders

animals that live in or on their food surfaces

fluid feeders

suck nutrient rich fluid from a living host

bulk feeders

most animals that eat large pieces of food


alternations waves of contraction and relaxation in the smooth muscles lining the alimentary canal that helps push food through the digestive system


ringlike valves that can close off the alimentary canal to regulate the passage of materials between compartments

oral cavity

the mouth and the first step of digestion

salivary glands

deliver saliva through the ducts to the oral cavity


an enzyme found in saliva that hydrolyzes starch and glycogen into polysaccharides in maltose


provides most of the protective effects of saliva


ball shaped mixture of food and saliva the tongue creates before swallowing


throat region that opens to two passage ways:
1. trachea
2. esophagus


flap of tissue that prevents food/water entering the trachea


stores food and