Organ (biology)

In biology, an organ is a group of tissues that work together in an organism. They specialise in particular vital functions. They create an organ system which, as a whole, is an organism.

These are examples of organs:

• Heart
• Lungs
• Brain
• Ear
• Eye
• Gall bladder
• Stomach
• Spleen
• Bones
• Pancreas
• Kidneys
• Liver
• Intestine
• Skin
• Uterus
• Bladder

Classification

Organelles > Cells > Tissues > Organs > Organ systems > Organism

Organ (biology) Media

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  The liver and gallbladder of a sheep

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  1905 diagram of the internal organs of human body

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  Relationship of major animal lineages with indication of how long ago these animals shared a common ancestor. On the left, important organs are shown, which allows us to determine how long ago these may have evolved.

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  The flower is the angiosperm's reproductive organ. This Hibiscus flower is hermaphroditic, and it contains stamen and pistils.

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  Strobilus of Equisetum telmateia