Photosynthesis- bio 20

6CO2+6H2O—>

6CO2+6H2O—>

6O2+C6H12O6

structure of the chloroplast

Membrane bound. Contains flattened membrane bound sacs known as thylakoids. A stack of thylakoids is called a granum

Where do light dependant reactions occur

In the thylakoid membrane

Where do light independent (c.b cycle, dark) reaction occur

The stroma

Imputs of LD reaction

Sunlight, water, ADP+Pi, NADP+

What does photo system 2 produce

ATP and 02

What does photosystem 1 produce

ATP and NADPH

LI reactions imput

ATP,NADPH,CO2

LD reaction produces…

PGAL→glucose, ADP+ Pi, NADP+

light waves: the greater the wave…

The less energetic the wave is

Blue and red wavelengths are

Absorbed and used to drive LD reactions

Green wavelengths are…

Reflected which gives chlorophyll its green colour

When chlorophyll absorbs light…

An electron is excited to a higher energy level. The electron is unstable and falls back down, releasing energy

What happens to chlorophyll when the primary electron acceptor traps an electron

Chlorophyll is oxidized and the e- acceptor is reduced

Wave lengths of the photosystems

PS1: 700nm PS2: 680nm

Which PS does Cyclic electron flow use

PS1

Steps of cyclic electron flow

Non cyclic electron flow uses

PS1 and PS2

Steps of non cyclic flow

The three stages of dark reaction

1. Co2 is fixed to RuBP which forms an unstable 6c molecule

2. The 6c molecule splits into two 3c molecules called PGA

3. PGA uses ATP as an energy source to remove hydrogen from NADPH, a new molecule (PGAL) is formed

Fates of PGAL

1. Used as an energy source

2. Combine with other PGAL to form glucose

3. Recycled to replenish RuBP

How many turns of the Calvin benson cycle does it take to produce 1 molecule of PGAL

3 turns (1CO2 used in each cycle)

What happens to the other 5 molecules of PGAL

Recycled to produce RuBP

How many turns of the Calvin benson cycle does it take to produce 1 glucose molecule

6 turns