Human Body

General Science · 6 min read · Sunitha Rao

Organ systems, blood, vitamins and deficiency diseases.

The human body is organised into systems. The heart has four chambers and pumps blood through arteries and veins; red blood cells carry oxygen using haemoglobin, while white blood cells defend against infection.

Digestion begins in the mouth with saliva and is completed in the small intestine, where most absorption occurs. The liver is the largest internal organ, and skin is the largest organ overall.

Vitamin deficiencies are a reliable exam topic: vitamin A protects vision, C prevents scurvy, D comes from sunlight and prevents rickets, and B12 deficiency causes anaemia.

Important points

  • The human heart has four chambers.
  • Red blood cells transport oxygen through haemoglobin.
  • Skin is the largest organ; the liver is the largest internal organ.
  • Vitamin D is synthesised with the help of sunlight.
  • Insulin is produced by the pancreas.

Examples

  1. Scurvy is caused by a lack of vitamin C, found in citrus fruits.
  2. Rickets in children indicates vitamin D deficiency.

Practise Human Body questions →