Photosynthesis: Outline Flashcards Preview

A2 Biology: Photosynthesis & Respiration > Photosynthesis: Outline > Flashcards

Flashcards in Photosynthesis: Outline Deck (23):
1

what is the overall equation for photosynthesis?

6CO₂ + 6H₂O (+ light) → C₆H₁₂O₆ + 6O₂

2

what is some of the light energy conserved in the form of?

chemical bonds

3

what are the 3 main stages of photosynthesis?

1. capturing of the light energy
2. the Light Dependent Reaction (LDR)
3. the Light Independent Reaction (LIR)

4

how is the light energy captured?

by chloroplast pigments (such as chlorophyll)

5

briefly summarise what happens during the LDR

- some absorbed light energy is conserved in chemical bonds
- electron flow is created by the effect of light on chlorophyll
- this causes water to split (photolysis) into protons (H⁺), electrons and oxygen
- the products are NADP, ATP and oxygen

6

briefly summarise what happens during the LIR

- protons (H⁺) are used to produce sugars and other organic molecules

7

what are the 2 purposes of the light energy during LDR?

1. to add an inorganic phosphate (Pᵢ) to ADP, to form ATP
2. (photolysis) light causes water to split into protons (H⁺) and hydroxide ions (OH⁻)

8

what is oxidation?

the process when a substance gains oxygen or loses hydrogen, and energy is given out

9

what is a substance said to be when it gains oxygen or loses hydrogen?

oxidised

10

what is reduction?

the process when a substance loses oxygen or gains hydrogen, and energy is taken in

11

what is a substance said to be when it loses oxygen or gains hydrogen?

reduced

12

when a substance is oxidised what happens to its electrons?

electrons are lost

13

when a substance is reduced what happens to its electrons?

electrons are gained

14

oxidation and reduction always take place together, what is this type of reaction called?

redox reaction

15

in eukaryotic plants, which organelle does photosynthesis take place in?

chloroplasts

16

what is the structure of grana?

stacks of many thylakoids

17

what is the structure of thylakoids?

disc-like structures

18

where is the photosynthetic pigment chlorophyll found?

within the thylakoids

19

what are inter-granal lamellae?

tubular extensions which join up some thylakoids with other thylakoids in adjacent grana

20

which stage of photosynthesis takes place in the grana?

LDR

21

what is the structure of the stroma?

a fluid-filled matrix

22

the stroma contains a number of other structures, give one example

starch grains

23

which stage of photosynthesis takes place in the stroma?

LIR