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Organization in the human body

Review your understanding of organization in the human body in this free article aligned to NGSS standards.

Key points:

  • The human body is a complex system made up of interacting parts. These parts include organ systems, organs, tissue, and cells.
  • Cells in the human body are specialized. This means that they have unique structures and functions.
  • A tissue is a group of similar, specialized cells. A tissue’s cells work together so that the tissue can do its job.
  • An organ is made up of multiple types of tissues. These tissues make up an organ’s structure, and also work together.
  • An organ system is a group of organs that work together to carry out complex tasks in the body.
  • The human body is made up of multiple organ systems. These organ systems interact to help the body grow and survive.
A diagram shows the levels of organization in the human body with arrows between each level. The first level shows a liver cell. The second level shows liver tissue, which is made up of multiple liver cells. The third level shows the liver, which is an organ. The last level shows that the liver is part of an organ system in the human body.
Cells make up tissues, which make up organs, which make up organ systems. Image created with Biorender.com.

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