Functions of Digestive System U.4 L.2

Monomer

Small molecules that group together to create a saccharide.

Components of digestion

Ingestion (taking in nutrients), Digestion (break down complex molecules into smaller ones), Absorption (transport of nutrients to body’s tissues), Egestion (removal of waste).

Ingestion

The process of taking in nutrients, beginning in the mouth.

Digestion

The process of breaking down complex molecules into smaller ones, occurring in the mouth, stomach, and intestines.

Absorption

The transport of nutrients to the body’s tissues, primarily occurring in the small intestine.

Egestion

The removal of waste, occurring through the anus and rectum.

Mechanical digestion

Physically breaking food into smaller pieces, used by teeth, tongue, palate, cheeks, and gizzard in some animals.

Chemical digestion

The breakdown of larger molecules by enzymes in saliva, stomach, and small intestine.

Enzymes

Proteins that help break down molecules, such as proteins into amino acids.

'ase'

A suffix indicating an enzyme (e.g., lipase, protease).

Bolus

Food mixed with saliva, no longer in its original state, becomes chyme in the stomach.

Salivary glands

Three pairs of glands that produce saliva, including parotid, sublingual, and submandibular glands.

Taste buds

Rough projections of the tongue that detect taste; evolved to help avoid poisonous foods.

Palate

The roof of the mouth, consisting of hard palate (bone) and soft palate (contains the uvula).

Pharynx

The common path of food and air, leading to the esophagus.

Epiglottis

A flap that covers the opening of the trachea while swallowing.

Peristalsis

Rhythmic, wavelike contractions that move the bolus of food through the digestive system.

Chyme

The milky substance formed in the stomach after food is mixed with gastric juices.

Pepsin

A protein-digesting enzyme that breaks down longer amino acid chains into shorter ones.

Hydrochloric acid (HCl)

A gastric secretion that kills harmful substances and activates pepsin from pepsinogen.