Biology
Part of speech: noun
Definition: The study of all living matter in all its forms, with respect to the living organism or groups of organisms. The forms of life in a place, their behavior and interaction, and the study thereof. The structure, function, and behavior of an organism or type of organism.
Example sentence: I've always been interested in science - one of my favourite books is James Watson's 'Molecular Biology of the Gene.'
Ecology
Part of speech: noun
Definition: The branch of biology dealing with the relationships of organisms with their environment and with each other.