UnScramble this Word: t g n e r a e s?

Questions

Botany & zoology combined make up the science of _______.?

Brahma, Vishnu & Shiva are gods in which religion?

Branch of biology concerned with the study of plants (kingdom plantae; plant)?

Branch of biology dealing with the development of the animal embryo?

Branch of mathematics that deals with the properties & relationships of numbers (number)?