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Flashcards in Photosynthesis Deck (27)
1

Balanced Chemical Equation for Photosynthesis

6Co2 + 6 H2O = C6H1206 + 6O2

2

Explain the benefits of a leaf having a large surface area.

The larger surface area the more chance of exposure to sunlight that it has.

3

What is the cuticle in a plant.

A waxy layer on outer surface of epidermal cells which prevents the leaf from loosing water.

4

Define Photosynthesis

Photosynthesis is the process where light energy is transformed into chemical energy and is stored as sugars.

5

What is the role of the stomata in a plant?

Provides access into the leaf for carbon dioxide.

6

What is the role f the xylem vessels?

Supply water form the roots to the cells of the leaf.

7

Where does photosynthesis occur?

Chloroplast

8

Define chlorophyll

Chlorophyll is a photosynthetic pigment which absorbs blue and red light. They reflect green, hence the colour of plants.

9

Which form of chlorophyll has direct involvement with photosynthesis?

Chlorophyll A

10

Why is it a benefit to have other pigments?

Other pigments such as chlorophyll b absorb light and transfer it to chlorophyll a, thus broadening the range of different wavelengths that can drive photosynthesis.

11

Where does the light-dependent stage occur?

Thylakoid Membrane

12

List inputs for the light dependent stage

-Sunlight
-Chlorophyll
-NADP
-ADP + Pi
-H20

13

List outputs for the light dependent stage

-ATP
-Oxygen (waste product)
-NADPH

14

Explain briefly what happens in the light dependent stage

1. Light energy is trapped in the chlorophyll causing electrons to become excited.
2. The electrons drive photolysis: The splitting of a water molecule into hydrogen ions, oxygen gas and electrons are also relased
3. NADP joins with a hydrogen ion to for NADPH
4. ADP+ Pi forms ATP

15

What drives the second stage of photosythesis

The NADPH AND ATP from the first stage/

16

What is the light independent stage also known as?

The Calvin Cycle

17

Inputs of the Calvin Cycle

NADPH
ATP
CO2

18

Outputs of the calvin cycle

Glucose
NADP
ADP + Pi

19

Briefly explain the steps of the calvin cycle

1. Co2 molecues in the stroma combine with a 5C compound called RuBP. The enzyme that joins these two is called RiBisCo. This is called carbon fixation
2. A 6C compound splits in 2 3C compounds
3. ATP and NADPH are used to rearrange the structre of the molecules in a number of steps to form 2 triosphosphate molecules.
4. A 3C sugar compound is released to form glucose.
5. The remaingin molecules reform RuBP

20

What are the main factors that affect the photosynthetic Rate?

-Light Intensity
-Temperature
-Co2 Concentration

21

What are the main parts in a chloroplast?

Thylakoid
Granum
Grana
Intermembrane Space
Outer Membrane
Inner Membrane
Stroma
Stroma Lamella
Starch Molecule
DNA

22

Word equation for photosynthesis

Carbon dioxide + water -------> (in the presecence of light (energy) and chlorophyll)) yields glucose and oxygen1

23

Define autotrophs

Self feeding organisms that synthesis their own organic molecules

24

Define hetertrphs

Animals receiving their energy from other organisms

25

Where does the LD stage occur?

Grana

26

Where does the LID occur

stroma

27

Photosynthesis is an

endergonic reaction