Year 9 Science: Cells, Organ Systems, and Energy Knowledge Organiser

Vocabulary flashcards covering Year 9 Science knowledge organisers on cell biology, cellular transport, organ systems, digestion, circulation, plant transport, energy stores, energy resources, and scientific investigations.

Diffusion

The spreading out of particles from an area of higher concentration to an area of lower concentration.

Active transport

The movement of substances from an area of low concentration to an area of high concentration (against a concentration gradient), which requires energy from respiration.

Osmosis

The movement of water through a partially permeable membrane, from a dilute solution to a more concentrated solution, requiring no energy.

Chemical store

The energy store that decreases when a battery is used or a fuel is burnt.

Kinetic store

The energy store that increases if an object speeds up, measured in joules ($J$) and increased by more mass or more speed.

Gravitational potential store

The energy store that increases if an object is lifted higher, measured in joules ($J$) and increased by more height or more mass.

Elastic potential store

The energy store that increases if a spring is stretched.

Thermal or internal store

The energy store that increases if an object is heated up.

Closed system

A group of objects whose total energy remains constant.

Dissipated energy

Energy that is wasted as heat to the surroundings.

Insulation

A method used to reduce energy dissipation from a hot object.

Lubrication

A method used to reduce energy dissipation from a moving object.

Non-renewable energy resources

Energy resources that are finite and cannot be replenished as they are used, including coal, oil, gas, and nuclear fuels.

Renewable energy resources

Energy resources that can be replenished as they are used.

Hydroelectric energy

An energy resource that uses water running downhill.

Geothermal energy

An energy resource that uses heat from underground.

Biofuels

An energy resource that uses plants for fuels.

Tidal energy

An energy resource that uses the daily movement of the sea.

Compare

To give similarities and differences.

Evaluate

To give advantages, disadvantages, and your own conclusion.

Arteries

Blood vessels that have thick, muscular walls.

Veins

Blood vessels that contain valves to prevent the backflow of blood.

Capillaries

Blood vessels with walls that are one cell thick to allow substances to diffuse in and out.

Ventricles

Chambers located at the bottom of the heart; the left pumps blood to the body, while the right pumps blood to the lungs.

Palisade mesophyll

The layer in the leaf where photosynthesis takes place, containing cells adapted with many chloroplasts.

Spongy mesophyll

The layer of the leaf that allows gasses to diffuse.

Stomata

Holes at the bottom of the leaf through which carbon dioxide enters, opened and closed by guard cells.

Xylem

Plant transport tissue that moves water upwards only, pulled by the transpiration stream.

Phloem

Plant transport tissue that transports sugars in both directions.

Transpiration

The loss of water vapour from the leaf, speeded up by higher temperature, more light, and more wind.

Independent variable

The variable that is changed (adjusted) in an investigation.

Dependent variable

The variable that is measured (and recorded) in an investigation.

Digestive system

The organ system that breaks down large insoluble molecules.

Active site

The region on an enzyme where the substrate binds in a 'lock and key' mechanism.

Denatured

The condition of an enzyme when its active site changes shape because the temperature is too high.

Carbohydrase

An enzyme that breaks carbohydrates down into sugars.

Protease

An enzyme that breaks down protein into amino acids.

Lipase

An enzyme that breaks down fats into fatty acids and glycerol.

Amylase

An enzyme that breaks starch into glucose.

Visking tubing

A semi-permeable material used to model the gut, permitting small molecules like glucose to pass through.

Iodine

A chemical reagent used to test for the presence of starch.

Benedict's

A chemical reagent used to test for the presence of glucose.

Bile

A digestive substance produced by the liver and stored in the gall bladder.

Eukaryotic cell

A cell that has a nucleus which contains the genetic information of the organism, such as plant and animal cells.

Prokaryotic cell

A cell that does not have a nucleus and stores its genetic information in the cytoplasm as a single looped chromosome, such as bacteria.

Plasmids

Extra genetic material in prokaryotic cells stored in small loops.

Cell cycle

A multi-step process that makes two genetically identical cells from one parent cell for growth and repair.

Stem cells

Undifferentiated cells that can form many different types of cells.

Meristem tissue

Plant tissue in which plant stem cells are found.