A layer of tissue in plants, located between the wood and the bark, that is responsible for the growth in thickness of roots and stems.

The evolutionary process by which a single species splits into two or more distinct species.

the formation or arrangement of a placenta in the uterus

The process of a fertilized egg developing into an embryo; in plants, this refers to the formation of the cotyledon, shoot, and root within a seed, while in animals it involves a series of cell divisions and specialization.

the formation of a blood clot inside a blood vessel