Level of life
Cell
The smallest unit that can live on its own. Every living thing is made of one or more cells.
Tissue
A group of similar cells working together, such as muscle, nerve or leaf tissue.Source: OpenStax, 2022Source: OpenStax, 2018
Level of life
How Tissue connects
Tissue is made of
Tissue makes up
Level of life
Organ
Several tissues combined into a structure with a particular job, such as the heart, a kidney or a leaf.
Studied in
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Sources & further reading
The explanations on this page are our own summaries of these sources. Follow a link to read the original; if anything here disagrees with it, the original wins. How we choose and check sources.
Anatomy and Physiology 2e (opens the original in a new tab)
OpenStax (2022). OpenStax, Rice University.
TextbookEducationalLicence: CC BY-NC-SA 4.0 (linked, not reused)
Biology 2e (opens the original in a new tab)
OpenStax (2018). OpenStax, Rice University.
Free introductory college textbook.
TextbookEducationalLicence: CC BY-NC-SA 4.0 (linked, not reused)