key word

Question 1

photosynthesis

Answer 1

A chemical reaction in green plants that uses sunlight to make food.

Question 2

chloroplast

Answer 2

An organelle containing chlorophyll found in some plant cells. The reactions of photosynthesis happen in chloroplasts.

Question 3

chlorophyll

Answer 3

A pigment that absorbs light and splits water into hydrogen and oxygen in the first stage of photosynthesis.

Question 4

enzyme

Answer 4

A protein with an active site that catalyses a chemical reaction.

Question 5

catalyst

Answer 5

A catalyst is a substance that increases the rate of a chemical reaction, but which is left unchanged by the reaction.

Question 6

active site

Answer 6

The part of an enzyme where the chemical reaction takes place. The reacting molecules fit into the active site.

Question 7

substrate

Answer 7

A substance that is changed by the action of a particular enzyme. each molecule of the substrate must be the correct shape to fit into the enzyme’s active site.

Question 8

optimum

Answer 8

The most favourable condition for an enzyme at which it catalyses a reaction at its fastest rate.

Question 9

Diffusion

Answer 9

The spreading out of molecules.

Question 10

Stomata

Answer 10

Tiny holes in the outer surface of a leaf enable a plant to exchange gases with its surroundings.

Question 11

Osmosis

Answer 11

The diffusion of water molecules from an area where they are in high concentration to an area where they are at lower concentration through a partially permeable membrane.

Question 12

partially permeable membrane

Answer 12

A membrane that acts as a barrier to some molecules but allows others to diffuse through freely.

Question 13

active transport

Answer 13

Molecules are moved in or out of a cell using energy.

Question 14

ATP

Answer 14

Adenosine triphosphate a substance made by cellular respiration.

Question 15

turgid

Answer 15

When a plant cell takes in water it bulges and becomes stretched.

Question 16

xylem

Answer 16

Plant tissue that transports water and dissolved minerals through a plant.

Question 17

phloem

Answer 17

A plant tissue that transports sugar through a plant.

Question 18

transpiration

Answer 18

The process of water movement through a plant and its evaporation from cells in the leaves.

Question 19

potometer

Answer 19

It is a device that measures the rate at which a plant draws up water.

Question 20

translocation

Answer 20

The process of moving sugars amino acids and other substances through a plant.

Question 21

producer

Answer 21

An organism that is able to make its own food.

Question 22

consumer

Answer 22

An organism that eats others in a food chain

Question 23

biomass

Answer 23

All the tissues that make up an organism.

Question 24

amino acid

Answer 24

Amino acids are joined in long chains to make proteins.

Question 25

carbohydrate

Answer 25

A substance made of carbon, hydrogen, and oxygen.

Question 26

lipid

Answer 26

A substance made from glycerol and fatty acids. Lipids are used for storage and making cell membranes

Question 27

interdependence

Answer 27

The size of a population of organisms affects and is affected by the sizes of other populations in an ecosystem.

Question 28

food chain

Answer 28

A model of the feeding relationships between populations of organisms.

Question 29

food web

Answer 29

A model of the feeding relationships between populations of organisms.

Question 30

competition

Answer 30

Organisms that require the same resources must compete for the resources

Question 31

decomposition

Answer 31

Process in which dead organisms are broken down and substances in their bodies are returned to the environment

Question 32

biotic

Answer 32

The living parts of an ecosystem.

Question 33

abiotic

Answer 33

The non-living parts of an ecosystem

Question 34

Carbon cycle

Answer 34

The natural processes that recycles carbon through the living and non-living parts of an ecosystem.

Question 35

water cycle

Answer 35

Processes that cycle water through the abiotic and biotic parts of an ecosystem.

Question 36

biotic factors

Answer 36

The living parts of an ecosystem that affect the distribution and abundance of organisms.

Question 37

abiotic factors

Answer 37

A non-living factor that can affect the distribution and abundance of living organisms

Question 38

bioaccumulation

Answer 38

An increase in the concentration of a substance in organisms in the higher trophic levels of a food chain.

Question 39

eutrophication

Answer 39

A type of environmental damage. Excess nitrate or phosphate in water causes rapid growth of algae followed by the death and decomposition of water plants.

Question 40

quadrat

Answer 40

A square grid of a known area that is used when measuring the abundance of non-moving or slow-moving organisms in a location

Question 41

transect

Answer 41

A technique used to measure the distribution and abundance of organisms at regular intervals along a straight line through an ecosystem

Question 42

representative sample

Answer 42

The characteristics of a representative sample are very similar to the characteristics of the whole population.