Science - Chapter 6 - The Digestive System

Ingestion

When food is taken into the mouth

Digestion

When food is broken down

Absorbtion

When digested food is passed into the blood and carried to cells

Assimilation

When digested food is used by the body for energy and to make new cells

Egestion

When the remnants of the food are released as waste

Physical Digestion

When food is broken down into smaller pieces by the teeth, tongue and churning motion of the muscles in the stomach

Chemical Digestion

When food is further broken by digestive enzymes and other stomach juices in the stomach, or by saliva in the mouth

Enzyme

A protein that speed up the rate of chemical reaction in cells and is not used up in the process

Incisors

The narrow sharp teeth at the front of the mouth used for cutting and slicing food

Canines

Pointed teeth used for grasping and tearing food, [also known as ‘eye teeth’]

Pre-molars

Large, rounded teeth used for crushing and grinding food

Molars

The largest teeth, found at the back of the mouth, used for crushing and grinding food

Amylase

An enzyme in saliva that chemically breaks down starch in food into the sugar maltose

Maltose

A sugar created by the breaking down of starch

Peristalsis

A wave-like movement of muscles in the oesophagus

Oesophagus

A muscular tube that connects the mouth to the stomach, [also know as the food pipe]

Stomach

An expandable muscular bag that physically churns food and serves as a temporary storage space

Maltase

A digestive enzyme that breaks down maltose into the smaller sugar glucose

Villi

The tiny, thread like projections that line the small intestine to increase surface area and allow nutrients from fully digested food to be absorbed into the bloodstream

Pancreas

Where digestive enzymes that are passed into the small intestine are produced

Liver

The largest internal organ in the body which produces bile, breaks down harmful substances like alcohol and keeps body temperature at 37 degrees Celsius

Bile

An alkaline fluid secreted by the liver, which aids in the digestion of fats in the small intestine

Small Intestine

Where food travels after the stomach, where it is completely digested and absorbed into the bloodstream

Large Intestine

A long tube-like organ, where fully digested food goes after the small intestine. The primary functions of the large intestine is to reabsorb water from fully digested food into the blood and prepare the food for egestion as faeces