Photosynthesis

Job of light in photosynthesis

Job of light in photosynthesis

Provides energy by exciting the electrons in the chlorophyll

Byproducts not used in photosynthesis

Oxygen from the H2O

What does a water molecule produce in photosynthesis?

Hydrogen (hydronium ions & electrons) and oxygen

Where do H + ions accumulate in the light reactions?

In the thylakoid lumen (acidic pH bc hydronium ions)

Overall, photosynthesis produces what 2 things?

Glucose and Oxygen

What do photosystems do?

PS2: split water
PS1: re-energizes the electrons

What does the Calvin cycle need that is provided by the light dependent reactions?

ATP and NADPH

Thylakoid

light dependent reactions

Stroma

Calvin cycle

Oxidation

releasing electrons

Reduction

gaining electrons

Photosynthesis energy conversion

Light into chemical energy

Autotroph

make their own food

Heterotroph

can't make their own food; rely on outside food source

What organism did photosynthesis first evolve in?

Cyanobacteria

Stomata: Structure, function, and gasses interchanged

Openings in bottom of leaf that allow CO2 to come in and O2 to leave

Thylakoids

stacks up

Chloroplast

site for photosynthesis

Stroma

aqueous internal fluid

Chlorophyll A

primary; blue/green

Chlorophyll B

accessory; yellow/green

Describe light reactions

Take light & convert into chemical energy

Describe the Calvin cycle

Turn CO2 into sugar

Describe photorespiration

Too hot and stomata close to not lose water

H+ (hydronium)

acidic

OH-

OH- basic

Role of ATP synthase and what powers it?

Proton gradient