Energy Transfer - Photosynthesis: Key Terms

Question 1

NADP

Answer 1

A molecule that carries electrons produced in the light-dependent reaction of photosynthesis

Question 2

Oxidation

Answer 2

Chemical reaction involving the loss of electrons

Question 3

Oxidation-reduction

Answer 3

Chemical reaction in which electrons are transferred from one substance to another substance

Question 4

Reduction

Answer 4

Chemical process involving the gain of electrons

Question 5

Stroma

Answer 5

Fluid-filled matrix of a chloroplast where the light-independent reaction of photosynthesis takes place

Question 6

Thylakoid

Answer 6

Series of flattened membranous sacs in a chloroplast that contain chlorophyll and the associated molecules needed for the light-dependent reaction of photosynthesis

Question 7

Metabolism

Answer 7

The chemical processes that occur within a living organism in order to maintain life

Question 8

Photolysis

Answer 8

Light energy splits 2 water molecules into 4 electrons, 4 hydrogen ions (protons) and an oxygen molecule (light-dependent reaction). These electrons replace the electrons lost from a chlorophyll molecule when light strikes it.

Question 9

Coenzyme

Answer 9

A non-protein compound that is necessary for the functioning of an enzyme

Question 10

Chloroplasts

Answer 10

The cellular organelles where photosynthesis takes place

Question 11

Chlorophyll

Answer 11

Photosynthetic pigment inside thylakoids which absorbs light energy

Question 12

Light-dependent reaction

Answer 12

Stage of photosynthesis in which light energy is required to produce ATP and reduced NADP

Question 13

Photoionisation

Answer 13

Process by which a chlorophyll molecule becomes ionised

Question 14

Proton pumps

Answer 14

A protein which actively transports protons into the thylakoid using energy from electrons from chlorophyll

Question 15

Electron transfer chain

Answer 15

How electrons are passed along a number of electron carriers in a series of oxidation-reduction reactions

Question 16

Chemiosmotic theory

Answer 16

Mechanism by which ATP is produced in the light-dependent stage of photosynthesis

Question 17

ATP synthase

Answer 17

An enzyme which is embedded in the thylakoid membrane through which protons pass through and cause changes to the structure of the enzyme which then catalyses the combination of ADP with inorganic phosphate to form ATP

Question 18

Light-independent reaction

Answer 18

Stage of photosynthesis which does not require light energy directly, but does need the products of the light dependent reaction to reduce CO2 and form carbohydrate

Question 19

Calvin cycle

Answer 19

A biochemical pathway (part of the light-independent reaction) where CO2 is reduced to form carbohydrate

Question 20

Ribulose Bisphosphate (RuBP)

Answer 20

A 5 carbon sugar (in the Calvin cycle) which reacts with carbon dioxide in the stroma to produce two molecules of GP

Question 21

Glycerate 3 phosphate (GP)

Answer 21

A 3 carbon acid (in the Calvin cycle) which reduced NADP is used to reduce to TP using energy supplied by ATP

Question 22

Triose phosphate

Answer 22

A 3 carbon sugar (in the Calvin cycle) which can be converted to organic substances that the plant requires such as starch, cellulose, lipids, glucose, amino acids and nucleotides, but most are used to regenerate ribulose biphosphate using ATP from the light-dependent reaction