Biology key terms

The controlled separation and dropping of a plant part, such as a leaf.

The movement of digested, soluble molecules from the small intestine into the body.

The number of organisms of a species in a particular area.

The change in lens shape that focuses light from near or distant objects onto the retina.

How close a measured result is to the true value or an accepted reference value.

Rain made more acidic than normal when acidic gases such as sulfur dioxide, released by burning coal and oil, dissolve in it. It can damage leaves, acidify lakes and erode buildings.

A characteristic developed because of environmental conditions rather than inherited genetic information.

A cap-like structure in the head of a sperm cell that contains enzymes used to break down substances in the egg's jelly coat.

The minimum energy needed to begin a chemical reaction.

The region of an enzyme to which its substrate binds.

The movement of substances against a concentration gradient using energy released by respiration.

Tuberculosis that is causing symptoms and can spread from a person with an infection in the lungs.

A feature that helps an organism survive in the conditions where it normally lives.

A hormone released by the pituitary gland that increases the permeability of kidney tubules to water.

A hormone released by the pituitary gland that increases the permeability of the kidney's collecting ducts to water.

A chemical messenger made by the adrenal glands that prepares the body for fight or flight.

A hormone released by the adrenal glands during fear or stress that prepares the body for rapid action.

A cloning method in which the nucleus of an adult body cell is inserted into an egg cell whose own nucleus has been removed.

A stem cell retained in a mature animal; adult stem cells in bone marrow can form many cell types, including blood cells.

An unwanted or harmful response caused by a medicine or treatment.

Describes a process that occurs in the presence of oxygen.

Decomposition in conditions where oxygen is available.

Respiration that uses oxygen and completely oxidises glucose.

A person who displays the characteristic or disorder being followed in a pedigree.

A nutrient-containing gel used as a surface on which microorganisms can be cultured.

A solid jelly containing nutrients on which microorganisms can grow.

The clumping together of pathogens when antibodies bind to their antigens, which makes the pathogens easier for phagocytes to destroy.