
The Lining of the Small Intestine
It was long assumed to be a passive tissue. Recent work has shown that the cells of the lining are covered by a membrane that actively digests foods and speeds nutrients into the blood

The Lining of the Small Intestine
It was long assumed to be a passive tissue. Recent work has shown that the cells of the lining are covered by a membrane that actively digests foods and speeds nutrients into the blood

Up from the Embryo
The process by which a fertilized egg cell evolves to a highly specialized organism has been revealed by brilliant techniques of experimental embryology

Gulliver was a Bad Biologist
Jonathan Swift's famous fantasy gives the modern biologist an opportunity to reflect upon the way living things are tailored to their environment

The Biology of Old Age
Senescence and death, which to man seem unavoidable, are not the rule among all species of living things