Human Body

Concept: Organ Systems of Our Body

• An organ is made with a group of tissues that perform specific functions in the body.
• The human body is built up of several organ systems that regulate all bodily functions.

Levels of organisation in our body:

Cell : A cell is the smallest unit of life. It is the structural and functional unit of the human body.

Tissue : A group of cells with similar structures and performing similar functions.

Organ : It consists of a group of tissues that carry out a particular function.

Organ System : A system consisting of a group of organs that work together to perform specific body functions.

Organism : A living thing capable of performing all life processes with the help of the organ systems.

There are six major organ systems present inside our body—

1. Circulatory System
2. Skeletal System
3. Nervous System
4. Respiratory System
5. Excretory System
6. Digestive System

Organ Systems	Parts of the organ system	Functions
Circulatory System	Heart Arteries Veins Blood capillaries	Helps in the circulation of blood. Carries oxygen and nutrients to the cells.
Skeletal System	Bones Joints	Helps in movement and locomotion. Helps in running, jogging and different kinds of physical activities.
Nervous System	Brain Spinal cord	Controls all kinds of body movements, body functions and thought processes.
Respiratory System	Nostrils Respiratory tubes Lungs	Helps in respiration. Helps to breathe in oxygen from the air and breathe out carbon dioxide.
Excretory System	Kidney Ureter Urinary bladder Urethra	Purifies blood by absorbing all toxic materials and excess water. Produces urine as an excretory product.
Digestive System	Esophagus Stomach Liver Pancreas Colon	Digests food. Absorbs nutrients from the food. Discharges undigested materials as faecal matter.

New Words

Did You Know?

Skin is the largest organ of the human body.

Our body has two kidneys, but surprisingly, we can survive with only one.

Other than bones, we also have muscles in the body that help in movement and locomotion.