General Science

Human Body Systems Explorer

Explore major body systems, their organs, diseases, and exam-relevant facts through an interactive body diagram.

Digestive System

The digestive system breaks down food into nutrients that the body uses for energy, growth, and cell repair. It includes the alimentary canal and accessory organs.

Diseases

Jaundice

Cause: Excess bilirubin in blood due to liver dysfunction or bile duct obstruction

Frequently asked in GK — caused by liver malfunction; bilirubin is a breakdown product of haemoglobin

Diarrhoea

Cause: Bacterial, viral or parasitic infection of the intestines; contaminated food/water

ORS (Oral Rehydration Solution) is the primary treatment — a common exam question

Peptic Ulcer

Cause: Helicobacter pylori bacteria or excessive NSAID use eroding the stomach lining

Barry Marshall and Robin Warren won the Nobel Prize (2005) for discovering H. pylori as the cause

Exam Facts

•Salivary amylase (ptyalin) acts in the mouth at pH 6.8 — digests starch to maltose
•HCl in stomach provides pH 1.5-2 — kills bacteria and activates pepsinogen to pepsin
•Bile salts from the liver emulsify fats (not a digestive enzyme — no chemical digestion by bile)
•Pancreatic juice contains trypsin, lipase, and amylase — acts in duodenum
•Villi and microvilli in the small intestine increase absorption surface area to ~250 sq m