Any of the alternative forms of a gene that may occur at a given locus on a chromosome.
Involving or reproducing by reproductive processes (as cell division, spore formation, fission or budding) that do not involve the union of germ cells or egg and sperm.
Relating to the partitioning and cycling of chemical elements and compounds between the living and nonliving parts of an ecosystem.
The amount of living matter.
Biological science when applied especially in genetic engineering and recombinant DNA technology.
The formation of two daughter cells from one parent cell, mitosis.
Metabolic processes which break down nutrients into usable energy.
Synthesis of organic compounds (as in living cells) by energy derived from chemical reactions.
A threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.
The sum of the processes whereby apparently indifferent cells, tissues and structures attain their adult form and function.
The interactions and relationships between organisms and their environment.
A category of population dispersal covering one-way movement out of the population area.
An organism composed of one or more cells containing visibly evident nuclei and organelles.
Changes in the genetic composition of a population through successive generations.
An enzymatically controlled anaerobic breakdown of an energy-rich compound.
Long hair-like extensions from the cell surface whose movement is used for locomotion.
A functional hereditary unit located at a particular point on a chromosome that controls or acts in the transmission of hereditary characteristics.
The process by which gene frequencies are changed.
A state of equilibrium between different but interrelated functions or elements, as in an organism or group.
Cell structure responsible for cellular respiration.
An organism living in, with or on another organism in which a parasite obtains benefits from a host that it usually injures.
The chemical process by which chlorophyll-containing plants use light to convert carbon dioxide and water into carbohydrates, releasing oxygen as a byproduct.
The biological science of essential and characteristic life processes, activities and functions.
A cellular organism (such as a bacterium or a blue-green alga) that does not have a distinct nucleus.
The physical and chemical processes by which an organism supplies its cells and tissues with the oxygen needed for metabolism and relieves them of the carbon dioxide formed in energy-producing reactions.
The separation of two alleles in a heterozygote when gametes are formed.