OUAT key terms

The branch of agriculture that deals with growing field crops and managing the soil on which they grow, including planting, fertilising, irrigation and harvesting practices.

The pattern in which crops are grown on a piece of land over time, such as a sequence or combination of crops chosen to suit soil, climate and market needs.

Growing two or more different crops together in the same field at the same time, often in separate rows, to use land, light and nutrients more efficiently.

The planned alternation of different crops on the same land across seasons or years, used to maintain soil fertility and break pest and disease cycles.

The capacity of a soil to supply the nutrients and physical conditions needed for healthy plant growth, influenced by organic matter, minerals and soil structure.

The conversion of atmospheric nitrogen gas into compounds plants can use, carried out industrially in fertiliser production or biologically by certain bacteria living in soil or in root nodules.

A genus of soil bacteria that invade the roots of leguminous plants, forming nodules in which they convert atmospheric nitrogen into ammonia usable by the host plant.

A plant of the pea family whose roots commonly host nitrogen-fixing bacteria in nodules, valued in farming for enriching soil nitrogen and for protein-rich seeds.

The loss of water vapour from plant surfaces, mainly through tiny leaf pores called stomata, which pulls water and dissolved minerals upward from the roots.

Small adjustable openings in the leaf surface, each bounded by two guard cells, through which carbon dioxide enters and oxygen and water vapour leave the plant.

The process by which green plants use light energy to combine carbon dioxide and water into sugars, releasing oxygen as a by-product and storing energy in chemical bonds.

The green pigment inside chloroplasts that absorbs light energy for photosynthesis and gives leaves and other plant parts their characteristic green colour.

The improved size, growth or yield often shown by offspring produced by crossing two genetically different parental lines, compared with either parent.

The deliberate development of new plant varieties with desired traits such as higher yield, disease resistance or better quality, through selection and controlled crossing.

The complete genetic makeup of an organism, or the specific combination of gene variants it carries, which together with the environment determines its observable traits.

The observable characteristics of an organism, such as height, colour or yield, resulting from the interaction between its genetic makeup and the environment.

A hoofed mammal with a multi-chambered stomach that ferments plant material with the help of microbes, and that chews regurgitated food as cud.

The largest chamber of a ruminant's stomach, where a dense population of microorganisms breaks down fibrous plant material by fermentation before further digestion.

Feed material that is high in fibre and relatively low in digestible energy, such as hay, straw or silage, needed to keep ruminant digestion healthy.

Feedstuff that is rich in energy or protein and low in fibre, such as grains or oilseed meals, given in measured amounts to supplement roughage.

The total amount of feed given to an animal over a stated period, balanced to supply the energy, protein, minerals and vitamins it needs.

The thick, antibody-rich first milk produced by a mammal after giving birth, which must be fed to the newborn soon after delivery to provide passive immunity.

Temporary protection against disease gained when an animal receives ready-made antibodies from another source, such as colostrum from its mother, rather than making its own.

The period during which a female mammal secretes milk from the mammary glands to feed her young, beginning at birth and lasting for a characteristic time.

An infectious disease that can be passed from animals to humans, such as rabies or brucellosis, making animal handling and food safety important public health concerns.

The administration of a preparation that stimulates an animal's immune system to resist a specific disease without causing the illness itself.

The enforced isolation of animals, plants or their products for a set period to prevent the spread of pests or infectious diseases to new areas or herds.

The managed care and feeding of young animals or fish from hatching or birth through the vulnerable early stages until they are ready for stocking or market.

A facility where eggs of fish or poultry are incubated under controlled conditions and the newly hatched young are held and cared for before release or transfer.

The very young stage of a fish, shortly after hatching and absorption of the yolk sac, when the fish is small and dependent on suitable fine food.

A young fish that has grown beyond the fry stage to roughly the size of a finger, ready for stocking into nursery or grow-out ponds.

The number of fish or other farmed animals kept per unit of water volume or area, a key management figure affecting growth, health and water quality.

The controlled farming of aquatic organisms such as fish, prawns and molluscs in ponds, tanks, cages or enclosures, rather than catching them from the wild.

The community of tiny drifting plants and animals in water, including algae and small crustaceans, which forms the base of the food chain in ponds and seas.

The over-enrichment of water with nutrients, often from fertiliser runoff, that causes excessive growth of algae and can reduce dissolved oxygen and harm fish.

The movement of water across a partially permeable membrane from a region of higher water concentration to one of lower water concentration, equalising the two sides.

A protein that speeds up a specific chemical reaction in living cells without being consumed, and whose activity depends on suitable temperature and pH.

The type of cell division that produces two daughter cells with the same chromosome number as the parent cell, used for growth and repair of body tissues.

A community of living organisms together with the non-living parts of their surroundings, such as soil, water and air, interacting as a functioning unit.