Agriculture - study of producing crops from the land, with an emphasis on practical applications
Anatomy - the study of the animal form, with an emphasis on human bodies
Astrobiology is the study of the origin, evolution, distribution, and future of life in the universe
Biochemistry - the study of the chemical reactions required for life to exist and function, usually a focus on the cellular level
Bioclimatology is the interdisciplinary field of science that studies the interactions between the biosphere and the Earth's atmosphere on time scales of the order of seasons or longer
Bioengineering - the study of biology through the means of engineering with an emphasis on applied knowledge and especially related to biotechnology.
Biogeography is the study of the distribution of biodiversity spatially and temporall
Bioinformatics - also classified as a branch of information technology (IT) it is the study, collection, and storage of genomic data
Biomathematics or Mathematical Biology - the study of biological processes through mathematics, with an emphasis on modeling.
Biomechanics - often considered a branch of medicine, the study of the mechanics of living beings, with an emphasis on applied use through artificial limbs, etc.
Biophysics - the study of biological processes through physics, by applying the theories and methods traditionally used in the physical sciences
Biotechnology - a new and sometimes controversial branch of biology that studies the manipulation of living matter, including genetic modification
Botany - the study of plants
Cell Biology - the study of the cell as a complete unit, and the molecular and chemical interactions that occur within a living cell.
Chronobiology is a field of biology that examines periodic (cyclic) phenomena in living organisms and their adaptation to solar and lunar related rhythms
Conservation Biology - the study of the preservation, protection, or restoration of the natural environment, natural ecosystems, vegetation, and wildlife
Cryobiology - the study of the effects of lower than normally preferred temperatures on living beings.
Cryptozoology - the study of mythical creatures.
Developmental Biology - the study of the processes through which an organism develops, from zygote to full structure.
Ecology - the study of the ecosystem as a complete unit, with an emphasis on how species and groups of species interact with other living beings and non-living elements.
Entomology - the study of insects
Environmental Biology - the study of the natural world, as a whole or in a particular area, especially as affected by human activity
Epidemiology - a major component of public health research, it is the study of factors affecting the health and illness of populations
Ethology - the study of animal behavior.
Evolution or Evolutionary Biology - the study of the origin and decent of species over time
Genetics - the study of genes and heredity.
Herpetology - the study of reptiles (and amphibians?)
Histology - The study of cells and tissue, a microscopic branch of anatomy.
Ichthyology - the study of fish
Macrobiology - the study of biology on the level of the macroscopic individual (plant, animal, or other living being) as a complete unit.
Mammology - the study of mammals
Marine Biology - the study of ocean ecosystems, plants, animals, and other living beings.
Medicine - the study of the human body in health and disease, with allopathic medicine focusing on alleviating or curing the body from states of disease
Microbiology - the study of microscopic organisms (microorganisms) and their interactions with other living things
Molecular Biology - the study of biology and biological functions at the molecular level, some cross over with biochemistry
Mycology - the study of fungi
Neurobiology - the study of the nervous system, including anatomy, physiology, even pathology
Oceanography - the study of the ocean, including ocean life, environment, geography, weather, and other aspects influencing the ocean. See Marine Biology
Ornithology - the study of birds
Paleontology - the study of fossils and sometimes geographic evidence of prehistoric life
Psychiatry - the study of diseases of the mind
Parapsychology - the study of paranormal phenomena
Pathobiology or pathology - the study of diseases, and the causes, processes, nature, and development of disease
Parisitology - the study of parasites and parasitism
Pharmacology - the study and practical application of preparation, use, and effects of drugs and synthetic medicines.
Physiology - the study of the functioning of living organisms and the organs and parts of living organisms