B4 Keywords

Front 1

A bacterial or fungal organism that causes decay

Back 1

Decomposer

Front 2

A chemical used to control fungal pests

Back 2

Fungicide

Front 3

A chemical used to control insect pests

Back 3

Insecticide

Front 4

A chemical used to control weeds - can be selective or non-selective

Back 4

Herbicide

Front 5

A general term used to describe a chemical used to control animal pests

Back 5

Pesticide

Front 6

A membrane that allows the free diffusion of some small solute molecules but not others

Back 6

Partially permeable

Front 7

A mineral made up of carbon and oxygen found in the shells of marine organisms and making up sedmentary rocks

Back 7

Carbonate

Front 8

A problem in plant growth caused by lack of a particular mineral

Back 8

Deficiency

Front 9

A renewable fuel of biological origin that can be used as a convenient source of energy

Back 9

Biofuel

Front 10

A term used to describe intensive agriculture when applied to rearing of animals

Back 10

Battery farming

Front 11

A way of displaying the relationship between organisms in a food chain by displaying the number of organisms at each trophic level

Back 11

Pyramid of numbers

Front 12

A way of displaying the transfer of energy in food chains starting with producers and working through the trophic levels to the top consumer

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Pyramid of biomass

Front 13

AN organism that speeds up decay by eating dead plant and animal material and increasing its surface area

Back 13

Detritivore

Front 14

An additive used to enrich soil in essential plant minerals

Back 14

Fertiliser

Front 15

An organic form of nitrogen that is excreted by organisms and can be formed by decay, Readily converted into ammonia in the soil

Back 15

Urea

Front 16

An organism such as a plant that can produce its own food from simple substance - usually by photosynthesis

Back 16

Producer

Front 17

An organism that derives its energy and nutrients from eating plants or other animals

Back 17

Consumer

Front 18

An organism that secretes enzymes to digest its food externally before absorbing the digestion products

Back 18

Saprophyte

Front 19

Any method that seeks to increase the eficiency of farming through the use of mechanisation, chemicals, artificial control of conditions or selective breeding

Back 19

Intensive farming

Front 20

Any process that leads to the reuse of materials

Back 20

Recycling

Front 21

Bacteria that can convert atmospheric nitrogen into amino acids

Back 21

Nitrogen-fixing bacteria

Front 22

Commonly used artificial fertiliser used to add nitrogen, phosphorous and potassium to the soil for plant growth

Back 22

NPK

Front 23

Dead and decaying plant and animal material

Back 23

Detritus

Front 24

Decomposed organic material that can be used as an organic fertiliser and soil conditioner

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Compost

Front 25

Describes the ability of a membrane to allow the free diffusion of a particular substance

Back 25

Permeable

Front 26

Farming without soil using tight control of conditions and nutrient supply in synthetic media

Back 26

Hydroponics

Front 27

Feeding by secretion of digestive enzymes and absorbing the digestion products

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Saprophytic nutrition

Front 28

Intensive agriculture applied to fish

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Fish farm

Front 29

Layer of cells one cell thick making up underside of leaf

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Lower epidermis

Front 30

Layer of cells that allows gases to permeate freely through leaf

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Spongy mesophyll

Front 31

Layer of columnar cells in leaf where most photosynthesis takes place

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Palisade mesophyll

Front 32

Light absorbing pigment found in chloroplasts

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Chlorophyll

Front 33

Openings in undrerside of leaf that allow transpiration to take place

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Stomata

Front 34

Pairs of cells in lower epidermis that regulate stomatal opening, water loss and gas exchange

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Guard cell

Front 35

Plants that have two seed leaves (not grasses)

Back 35

Dicotyledonous

Front 36

Preventing or slowing the decay of food by decomposers through artificial means

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Food preservation

Front 37

Simple substances such as salts that carry elements that are needed by plants in addition to carbon, hydrogen and oxygen

Back 37

Minerals

Front 38

Soil bacteria that convert ammonia into nitrate which plants can absorb through their roots

Back 38

Nitrifying bacteria

Front 39

Soil bacteria that remove nitrogen from the main nitrogen cycle by breaking down nitrates into nitrogen gas

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Denitrifying bacteria

Front 40

Term that describes a plant cell that has lost water by osmosis

Back 40

Flaccid

Front 41

Term used to describe agriculture that avoids the use of chemicals and other intensive methods

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Organic farming

Front 42

Term used to describe the wrinkly appearance of an animal cell that has lost water due to osmosis

Back 42

Crenation

Front 43

The bursting of a cell due to rupture of the cell membrane

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Lysis

Front 44

The collected waste products of a population made up of faeces and urine

Back 44

Sewage

Front 45

The elimination of undigested food in the form of faeces

Back 45

Egestion

Front 46

The form taken by the vascular tissue of a plant in a leaf - provides support as well as allowing transport of water, minerals, sugars and other substances

Back 46

Vein

Front 47

The hollow centre of a tissue such as the xylem

Back 47

Lumen

Front 48

The layer of cells that make up the upper surface of a leaf

Back 48

Upper epidermis

Front 49

The loss of water vapour from the leaves of a plant that contributes to the flow of water from the roots

Back 49

Transpiration

Front 50

The name given to each layer in a food chain - usually no more than five

Back 50

Trophic level

Front 51

The net movement of water from a region of high to low water potential across a partially permeable membrane

Back 51

Osmosis

Front 52

The plant tissue that comprises the phloem and xylem

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Vascular bundle

Front 53

The process by which sugars are transported through the plant from the sources in the leaves to the sink organs such as roots and flowers

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Translocation

Front 54

The process whereby bacteria and fungi break down complex organic molecules into simpler substances that they can absorb

Back 54

Decay

Front 55

The result of a plant cell absorbing water by osmosis causing the cell contents to expand and press against the cell wall. Maintains plant stem rigidity.

Back 55

Turgid

Front 56

The result of a plant cell losing too much water by osmosis. The cell contents may separate from the cell wall

Back 56

Plasmolysis

Front 57

The situation when the concentration of a particular substance is higher on one side of the cell membrane than the other

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Concentration gradient

Front 58

The total mass of organic material - usually measured when dry to correct for different amounts of water

Back 58

Biomass

Front 59

The use of one species - usually introduced - to control another

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Biological control

Front 60

The vascular tissue in a plant that carries sugars, amino acids and other important nutrients from the leaves

Back 60

Phloem

Front 61

The vascular tissue in a plant that carries water and minerals from the roots to the leaves

Back 61

Xylem

Front 62

Uptake of substances into a cell against a concentration gradient. Requires energy

Back 62

Active transport

Front 63

Waxy layer on upper epidermis of leaf

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Cuticle

Front 64

What happens to a plant when its cells lose turgor pressure due to a lack of water

Back 64

Wilt