Sometimes it’s easy to tell if something is living or not. A teddy bear might look like a bear, but it cannot do any of the seven things it needs to be able to do to count as being alive.

Take the evolution of sex, for instance. To make the move from asexual to sexual reproduction, nature took a system by which parent cells reproduced simply by dividing (asexual reproduction ...

The five phases of mitosis and cell division tightly coordinate the movements of hundreds of proteins. How did early biologists unravel this complex dance of chromosomes? The most obvious ...

How sexual reproduction came about has long been a mystery, but an evolutionary model suggests it could have started with ...

In most multicellular organisms, meiosis is restricted to germ cells that are set aside in early development. The germ cells reside in specialized environments provided by the gonads, or sex organs.

The fluids provide the sperm cells with nutrients ... A penis goes into the vagina during sexual reproduction. This is also where menstrual blood leaves the body and where a baby exits during ...

Researchers at the Francis Crick Institute have found that the small intestine grows in response to pregnancy in mice. This ...

Both cells are essential components of the process ... Implications for the future of reproduction By simulating the microenvironment of mouse testes, the researchers aimed to create optimal ...