Biological clock may refer to:
- Circadian rhythm, living organisms' adaptations to solar related rhythms
- Age and female fertility
Famous quotes containing the words biological and/or clock:
“Although there is no universal agreement as to a definition of life, its biological manifestations are generally considered to be organization, metabolism, growth, irritability, adaptation, and reproduction.”
—The Columbia Encyclopedia, Fifth Edition, the first sentence of the article on “life” (based on wording in the First Edition, 1935)
“They’ll take suggestion as a cat laps milk;
They’ll tell the clock to any business that
We say befits the hour.”
—William Shakespeare (1564–1616)