All of the branches of life science?

The three main branches of Biology are:

botany - the study of plants

zoology - the study of animals, including classification, physiology, development, and behavior (See also Entomology, Ethology, Herpetology, Ichthyology, Mammology, and Ornithology)

Microbiology - the study of microscopic organisms (microorganisms) and their interactions with other living things