Edexcel GCSE Biology Key Terms

Excessive fat storage specifically located around the midsection and vital organs, carrying a high risk of metabolic diseases.

The non-living parts of an ecosystem that shape the environment, such as temperature, light intensity, or carbon dioxide levels.

A non-living physical or chemical part of an ecosystem, such as light intensity, temperature, or soil pH.

The non-living components of an ecosystem, such as temperature, light intensity, or water availability.

The natural detachment of parts of a plant, typically dead leaves and ripe fruit.

A specific layer of cells at the base of a leaf stalk where detachment occurs due to the breakdown of cell walls.

Determining a specific numerical age (in years) for an object or event.

The total number of individuals of a particular species living within a given area.

To allow an organism to adjust to a change in its environment (such as a new light intensity) before starting measurements.

The process by which the eye's natural lens changes shape to focus on objects at varying distances.

A dangerous condition caused by the accumulation of acid or carbon dioxide in body fluids when waste removal is insufficient.

Features developed during an organism's lifetime due to environmental influence, which cannot be inherited.

A specialised vacuole located at the front tip of a sperm cell that contains digestive enzymes to break down the egg's protective layers.

The minimum energy required for a reaction to occur; enzymes lower this to speed up reactions.

Protection against a disease achieved by the body actively producing its own antibodies and memory cells.

The specific region of an enzyme where the substrate binds and the chemical reaction occurs.

The movement of substances across a cell membrane against a concentration gradient, requiring energy from respiration.

A nitrogenous base that always pairs with Thymine.

A hormone released by the pituitary gland that regulates water reabsorption in the kidneys by changing the permeability of the collecting duct.

Endocrine glands located directly above the kidneys that secrete adrenalin into the bloodstream.

A hormone produced by the adrenal glands that prepares the body for rapid physical action in response to stress or danger.

A hormone released by the adrenal glands in response to stress or fear; unlike thyroxine, it is not controlled by negative feedback.

Multipotent stem cells found in specific tissues, like bone marrow, that can only differentiate into a limited range of cell types.

A different version of a gene that gives an organism a survival benefit in a specific environment.

A variant of a gene that increases an individual's likelihood of survival and reproduction in its specific environment.

Bacteria that require oxygen for respiration; during eutrophication, they consume dissolved oxygen while decomposing dead organic matter.

A chemical reaction in cells that uses oxygen to break down nutrient molecules, releasing a relatively large amount of energy for metabolic processes.

The wider blood vessel that brings blood into the glomerulus.

A Petri dish containing a nutrient-rich gel used to culture microorganisms in a laboratory.

Petri dishes containing a nutrient medium used to culture and grow microorganisms in a laboratory.