Biology Sem 2 Test 1 - Dig. System Only

Digestive system

System that supplies body cells with nutrients from food.

Digestive process steps

Ingestion, digestion, absorption, elimination.

Ingestion

Eating or intake of food.

Digestion

Breakdown of food into smaller nutrient molecules.

Absorption

Movement of nutrients into body cells.

Elimination

Removal of solid wastes from the body.

Mechanical digestion

Physical breakdown of food such as chewing and stomach churning.

Chemical digestion

Breakdown of food using enzymes and acids.

Digestive tract organs

Mouth, esophagus, stomach, small intestine, large intestine, rectum, anus.

Peristalsis

Wave-like muscle contractions that push food through the digestive tract.

Digestive tract lining

Epithelial tissue containing goblet cells that produce mucus.

Mucus

Substance that protects digestive cells and allows food to move smoothly.

Mouth

Organ where digestion begins through chewing and saliva.

Saliva

Fluid that softens food and contains digestive enzymes.

Amylase

Enzyme in saliva that breaks down starch.

Esophagus

Muscular tube that moves food from mouth to stomach.

Epiglottis

Flap that closes airway during swallowing to prevent food entering lungs.

Stomach

Organ that stores food and performs mechanical and chemical digestion.

Stomach mechanical digestion

Churning of food by stomach muscles.

Hydrochloric acid

Chemical that denatures proteins and kills bacteria.

Pepsin

Enzyme that breaks down proteins.

Small intestine

Long tube where final digestion and absorption occur.

Small intestine sections

Duodenum, jejunum, ileum.

Duodenum

First section where food mixes with digestive enzymes from liver, pancreas and gallbladder.

Jejunum and ileum

Areas where nutrients are absorbed into the bloodstream.

Villi

Hair-like projections that increase surface area for absorption.

Large intestine (colon)

Absorbs water, vitamins and salts from undigested food.

Rectum

Stores feces before elimination.

Anus

Opening where feces exit the body.

Accessory organs

Salivary glands, liver, gallbladder, pancreas.

Liver

Produces bile to break down fats.

Gallbladder

Stores bile and releases it into the small intestine.

Pancreas

Produces digestive enzymes and insulin.

Salivary glands

Produce saliva released into the mouth.