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We’ve got loads of key subject terms in our subject glossaries. There are three ways of finding what you are looking for:

  • First click on the letters of the alphabet to browse for terms.
  • Select a subject from the drop-down menu above to filter the terms by Subject.
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Here are some examples of the kinds of definitions you’ll find on this page.

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endocrine gland situated on top of each kidney, which produces hormones in response to stresses...


parenchyma cells with large air spaces to facilitate floating.


cellular respiration that takes place in the presence of free oxygen.


when an animal is dormant during hot and dry conditions.


the branch of the renal artery which carries blood to the nephron, and branches to form the...