Life science, also known as biological science or biology, is a branch of science that focuses on the study of living organisms and their processes. It encompasses a wide range of disciplines that explore the various aspects of life, including its origin, structure, function, behavior, and evolution.

The field of life science includes several sub-disciplines, such as:

1. Molecular Biology: This branch investigates the structure, function, and interactions of biological molecules, including DNA, RNA, proteins, and other macromolecules. It explores the mechanisms of gene expression, genetic regulation, and the molecular basis of cellular processes.
2. Genetics: Genetics is concerned with the study of heredity, variations, and inheritance of genes and traits in living organisms. It examines the transmission of genetic information from one generation to the next and explores the principles of genetic variation, gene expression, and genetic disorders.
3. Cell Biology: Cell biology focuses on the structure, function, and behavior of cells, which are the basic building blocks of life. It investigates cell organelles, cellular processes, cell division, and the interactions between cells and their environment.
4. Physiology: Physiology examines the normal functioning of living organisms, including the study of organ systems, their interactions, and how they maintain homeostasis. It investigates various physiological processes, such as respiration, circulation, digestion, and reproduction.
5. Ecology: Ecology explores the interactions between living organisms and their environment. It studies ecosystems, populations, communities, and the interrelationships among organisms and their habitats. Ecologists investigate topics such as biodiversity, conservation, and the impact of human activities on ecosystems.
6. Evolutionary Biology: Evolutionary biology focuses on the study of the origin and change of species over time. It explores the mechanisms of genetic variation, natural selection, adaptation, and speciation, providing insights into the diversity of life forms on Earth.