human body

Table of Contents

References & Edit History Quick Facts & Related Topics

Images, Videos & Interactives

How are different systems of the human body connected?

How much air do you breathe in a lifetime?

Human anatomy. Lists of body parts, systems, and organs.

human body

Q: What is the chemical composition of the human body?

Chemically, the human body consists mainly of water and organic compounds—i.e., lipids, proteins, carbohydrates, and nucleic acids. The human body is about 60 percent water by weight.

Q: What are the four main types of tissue in the human body?

The four main types of tissue in the human body are epithelial , muscle , nerve , and connective .

Q: What are the nine major organ systems in the human body?

The nine major organ systems in the human body are the integumentary system, the musculoskeletal system, the respiratory system, the circulatory system, the digestive system, the excretory system, the nervous system, the endocrine system, and the reproductive system.

Written and fact-checked by The Editors of Encyclopaedia Britannica

Last Updated: Dec 10, 2024 • Article History

Key People:: Galen; Andreas Vesalius; Mondino De’ Luzzi; Alcmaeon; Jonathan Miller

Related Topics:: human nervous system; human eye; human digestive system; human respiratory system; renal system

See all related content

What is the chemical composition of the human body?

What are the four main types of tissue in the human body?

What are the nine major organ systems in the human body?

News •

New method detects unrecognized chemicals in the human body • Dec. 7, 2024, 4:56 AM ET (News-Medical)

Scientists Publish Version of a Map of Human Body Cells • Dec. 2, 2024, 4:22 AM ET (Voice of America)

human body, the physical substance of the human organism, composed of living cells and extracellular materials and organized into tissues, organs, and systems. Human anatomy and physiology are treated in many different articles. For detailed discussions of specific tissues, organs, and systems, see human blood; cardiovascular system; human digestive system; human endocrine system; renal system; skin; human muscle system; nervous system; human reproductive system; human respiration; human sensory reception; and human skeletal system. For a description of how the body develops, from conception through old age, see aging; growth; prenatal development; and human development. For detailed coverage of the body’s ...(100 of 2443 words)

Access the full article

Help support true facts by becoming a member.