Digestion in animals begins in the A) intestines. B) mouth. C) stomach. D) throat.

B

Explanation:

mouth.

It begins as soon as the animal consumes food as the mouth enzymes start their working on the food. Chemical digestion continues as the food moves through stomach and then goes to small intestine where digestion process is completed.

Animals, for the most part, ingest their food as large, complex molecules that must be broken down into smaller molecules (monomers) that can then be distributed throughout the body of every cell. This vital function is accpomplished by a series of specialized organs that comprise the digestive system.

But Single-celled organisms can directly take in nutrients from their outside environment. Multicellular animals, with most of their cells removed from contact directly with the outside environment, have developed specialized structures for obtaining and breaking down their food. Animals depend on two processes: feeding and digestion.

Food for the most part consists of various organic macromolecules such as starch, proteins, and fats. These molecules are polymers made of individual monomer units. Breaking these large molecules into smaller components involves:

-Movement:

propels food through the digestive system

-Secretion:

release of digestive juices in response to a specific stimulus

-Digestion:

breakdown of food into molecular components small enough to cross the plasma membrane

-Absorption:

passage of the molecules into the body's interior and their passage throughout the body

-Elimination:

removal of undigested food and wastes

Three processes occur during what we loosely refer to as "digestion".