Edexcel IGCSE Biology Revision - Key Vocabulary

Flashcards covering key vocabulary from the Edexcel IGCSE Biology revision booklet, focusing on sections 1 (The nature and variety of living organisms) and 2 (Structure and functions in living organisms).

Movement

The capacity to move or change position, often involving the expenditure of energy.

Nutrition

The process of consuming nutrients and converting them into energy and body mass.

Sensitivity

The ability to detect and respond to changes in the environment (stimuli).

Excretion

The process of removing waste products of metabolism from the body.

Reproduction

The process of producing offspring, either sexually or asexually.

Respiration

The process of obtaining energy from food, either aerobically (with oxygen) or anaerobically (without oxygen).

Growth

The process of changing and developing over time.

Homeostasis

The maintenance of a stable internal environment.

Eukaryotic

Organisms whose cells contain a nucleus and other membrane-bound organelles.

Prokaryotic

Organisms whose cells do not contain a nucleus or other membrane-bound organelles.

Pathogen

A biological agent that causes disease or illness to its host.

Organelle

A membrane-bound structure within a cell that performs a specific function.

Cell differentiation

The process by which cells become specialized for particular functions.

Stem cells

Undifferentiated cells that can differentiate into specialized cells and can divide to produce more stem cells.

Embryonic stem cells

Stem cells derived from embryos that have the potential to differentiate into any type of cell in the body.

Adult stem cells

Stem cells found in adult tissues that can differentiate into a limited range of cell types.

Catalyst

A substance that speeds up a chemical reaction without being used up in the reaction itself.

Enzyme

A biological catalyst, typically a protein, that speeds up specific biochemical reactions in living organisms.

Active site

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

Substrate

The substance on which an enzyme acts.

Optimum

The point at which something is most effective

Denature

A permanent change in the three-dimensional structure of a protein or enzyme, causing it to lose its function.

Diffusion

The net movement of particles from an area of higher concentration to an area of lower concentration down a concentration gradient due to random motion.

Osmosis

The movement of water molecules from a region of higher water potential to a region of lower water potential through a semi-permeable membrane.

Active transport

The movement of substance across a cell membrane against a concentration gradient, requiring energy input.

Photosynthesis

The process by which plants convert light energy into chemical energy in the form of glucose.

Limiting factor

A factor that limits the rate of a process when it is in short supply.

Respiration

The process by which living organisms obtain energy from food by breaking it down into simpler substances.

Aerobic respiration

Respiration using oxygen to break down glucose completely into carbon dioxide and water, releasing a large amount of energy.

Anaerobic respiration

Respiration without oxygen, breaking down glucose incompletely and releasing a smaller amount of energy.

Gas exchange

The exchange of gases (oxygen and carbon dioxide) between an organism and its environment.

Alveoli

The tiny air sacs in the lungs where gas exchange occurs.

Ingestion

The act of taking food or drink into the body by the mouth.

Digestion

The breakdown of large, insoluble food molecules into smaller, soluble molecules that can be absorbed into the bloodstream.

Absorption

The process of taking digested food molecules into the blood stream.

Assimilation

The process of using absorbed food molecules and incorporating them into the cells of the body.

Egestion

The removal of undigested or unabsorbed material from the body.

Peristalsis

A wave of muscle contractions that pushes food (bolus) through the digestive tract.

Pneumonia

An inflammation of the lung tissue

Emphysema

Lung condition where the aveoli are damaged.

Excretion

Process by which living organisms eliminate waste products formed through metabolism.

Reflex Arc

A coordinated and involuntary response to an external stimulus

Surface area to volume ratio

This is a measure of the available surface area relative to the size of a cell or organism.

Xylem

Transports water and minerals from the roots to the aerial parts of the plant.

Phloem

Transports organic nutrients from the leaves to other parts of the plant.

Transpiration

The process by which water is lost from the aerial parts of a plant.

Coordination and response

The process by which animals and plants respond to changes in the environment.