Year 8 GL Science Assessment Revision Flashcards

A comprehensive set of vocabulary flashcards based on the Year 8 Science GL Assessment Revision Guide, covering key concepts in Biology, Chemistry, Physics, and Scientific Skills.

Food Web

A diagram showing feeding relationships where arrows indicate the direction of energy flow (from the organism being eaten to the consumer).

Competition

The interaction between two organisms that rely on the same food source or resource.

Producers

Organisms (plants/wheat) at the start of a food chain that make their own food via photosynthesis and are not consumers.

Aerobic Respiration

A process in the mitochondria of all living organisms that uses oxygen to convert glucose into carbon dioxide, water, and a large amount of energy.

Anaerobic Respiration

A less efficient process that breaks down glucose without oxygen, producing lactic acid in muscles or used by bacteria to release a small amount of energy.

Photosynthesis

The process by which plants, algae, and some bacteria convert light energy, carbon dioxide, and water into chemical energy stored in glucose and oxygen.

Chlorophyll

A green pigment found in chloroplasts that absorbs light energy for photosynthesis.

Stomata

Tiny pores on the underside of leaves that allow carbon dioxide to diffuse into the plant.

Bile

A substance produced by the liver that helps digest fats.

Alveoli

Small air sacs in the lungs that serve as the site of gas exchange where $O_2$ enters and $CO_2$ exits the blood.

Diffusion

The random movement of particles from an area of high concentration to an area of low concentration without using energy.

Levels of Organisation

The hierarchical structure of life: Cells $\rightarrow$ Tissues $\rightarrow$ Organs $\rightarrow$ Systems $\rightarrow$ Organism.

Anther

The part of a flowering plant that produces pollen grains, which are the male gametes.

Stigma

The part of a flowering plant that collects pollen grains during pollination.

Inherited Characteristics

Traits passed from parents to offspring via genes in DNA, such as eye colour and blood type.

Atom

The smallest unit of an element that retains its chemical properties, containing protons, neutrons, and electrons.

Molecule

A substance made of two or more atoms chemically bonded together.

Element

A pure substance made of only one type of atom that cannot be broken down by chemical means.

Compound

A substance formed from two or more different elements chemically bonded together in fixed ratios.

Physical Change

A usually reversible change where no new substance is formed, such as melting, freezing, or dissolving.

Chemical Change

An often irreversible change where a new substance is formed, such as burning, rusting, or neutralisation.

Metalloids

Elements found along the staircase boundary of the periodic table that have intermediate properties between metals and non-metals.

Mantle

The thickest layer of the Earth, located below the crust, made of semi-molten rock.

Metamorphic Rock

Rock formed when sedimentary rock is subjected to intense heat and pressure.

Displacement Reaction

A chemical reaction where a more reactive metal takes the place of a less reactive metal in its compound.

Net Force

The combined effect of all forces acting on an object; calculated by adding forces in the same direction or subtracting opposite forces.

Kinetic Energy

The energy possessed by moving objects, calculated as $KE = \frac{1}{2}mv^2$.

Refraction

The bending of light as it passes from one medium to another of a different density.

Amperes (A)

The unit of measurement for electric current, measured using an ammeter in series.

Electromagnet

A temporary magnet created by passing electric current through a coiled wire wrapped around an iron nail.

Independent Variable

The variable that is changed or controlled in a scientific experiment to test its effects on the dependent variable; plotted on the X-axis.

Dependent Variable

The variable that is tested and measured in a scientific experiment; plotted on the Y-axis.

Control Variable

Variables that are kept the same throughout an experiment to ensure a fair test.

Conclusion

The scientific step following data analysis and graphing where patterns in the data are used to support or reject a hypothesis.