quest on light reactions and photosynthesis

Chlorophyll

Green pigment essential for photosynthesis.

Carotene

Orange pigment that aids in photosynthesis.

Xanthophyll

Yellow pigment involved in light absorption.

Cyanophyll

Blue pigment that captures light energy.

Stroma

Liquid in chloroplast for light-independent reactions.

Thylakoid

Flattened sac in chloroplast where light reactions take place

Photon

a package of light that can act like a wave or a particle ROYGBIV

Light Reactions

Phase requiring light, water, NADP. phosphate

Dark Reactions

Phase not requiring light, occurs in stroma, requres NADP, CO2 and RUDP

G3P

3-carbon sugar produced in dark reactions.

NADP

Hydrogen carrier involved in light reactions.

Calvin Cycle

Dark reactions. Series of reactions to fix carbon dioxide.

RUBP

5-carbon sugar that initiates the Calvin Cycle.

3-Phosphoglycerate

Intermediate product formed during carbon fixation.

1,3-Biphosphoglycerate

Converted from 3-phosphoglycerate with ATP.

Rubisco

an enzyme that catalyzes the reaction that joins carbon dioxide into the calvin cycle.

Photorespiration

Process that limits sugar production in plants.

C4 Pathway

Alternative carbon fixation method in hot climates.

CAM Plants

Plants that fix CO2 at night to reduce water loss.

PEP Carboxylase

Enzyme with high affinity for carbon dioxide.

Bundle Sheath Cells

Specialized cells in C4 plants for carbon fixation.

Products of Light Reactions

Oxygen, ATP, and NADPH generated from light.

Requirements for Dark Reactions

ATP, NADPH, CO2, and RUBP needed for synthesis.

how does the calvin cycle work

to make one molecule of 3-carbon G3p, the cycle must take place 3 times incorparating 3CO molecules

Products of light dependent reactions

ADP, Phosphate, Carbohydrate, NADP

The light reactions convert

light energy into chemical energy (ATP and NADPH)

The dark reactions use

chemical energy to (ATP and NADPH) to produe G3P which are turned into complex organic compounds (C6H1206)

NADPH reduces

becomes G3P

phase one of light independent reactions

Carbon fixation: CO2 gets attached to a 5 sugar named ribulose bisphospha. It makes a 6 carbon intermediate that is really unstable that is splits in half forming 2 molecules of 3-phosphoglycerate

phase 2 of light indepednedt reactions

each 3-phosphoglycerate receives an additional phosphate group from ATP and turns into 1,3 biphsophoglycerate

phase 3 of light indpedent reactions

regeneration of RUBP

for every 3 CO2 that enters into the system,

6 molecules of G3P are formed…but only one molecule can be counted as a net gain.

Charecterstics of the C4 plant

has an alternative mode of carbon fixation, advantges in hot regions with sunlight, contains PEP carboxylases, has unqiue leaf anatomy

CAM plants and the C4 pathway prevent what from entering plants

Carbon dioxide

CAM plants and the C4 pathway found a way too?

minimize water loss during the day