• embedded in thylakoids of chloroplast
• absorb violet, blue, and red wavelengths
• reflects green
• types: a, b, and c 

• embedded in thylakoid membranes
• function as a antioxidant, and accessory prigments (broaden the range of light used for photosynthesis) 
• groups include carotenes, and xanthophylls
• in all chloroplasts and cyanobacteria 

• phycobillins -what are they, and where are they found. What are they soluble in? 

• accessory pigments
• found in cyanobacteria and chloroplasts of red algae 
• water soluble

1. energy-transduction reactions or light reactions - light is used to form ATP, and reduce e- carrier molecules. water split and oxygen is released
2. carbon fixation or dark reactions - energy of ATP used to link CO2 to organic mol. NADPH used to reduce carbon to simple sugar 

• antenna complex
• reaction center 
• photosystem I P700
• Photosystem II P680
• linked by ETC 

light reactions:

1. where do the electrons flow. and is it cyclic or non
2. what is oxidized 
3. what is reduced 
4. what form is the energy produced (2 molecules) 

1. electrons flow from water thru PII, PI, to NADP+, noncyclic
2. water is oxidized
3. NADP+ reduced to NADPH
4. energy form is 6 ATP, and 6 NADPH

• done at PI alone 
• generates ATP 
• Doesnt release O2 or reduce NADP+
• must occur to provide ATP to drive Calvin cycle and other processes. 

C3 pathway -

- what is the first detectable product, how many  

  carbons. 

- what cycle is it part of 

- what does it start and end with (same molecule)

- how many stages 

- PGA - 3 carbons

- calvin cycle

- start and ends with RuBP

- three stages 

C3 pathway - what is immediate product. 

- where else is this formed

- what can it be converted to if it is transported to

  cytosol?

- what about if it stays in chloroplast?

- what happens at night with sucrose  

- immediate product is PGAL

- can be converted to sucrose

- can be converted to starch

- at night sucrose is transported to other parts of the plant 

photorespiration

- what does rubisco have affinity for 

- it it catalyzes O2, what has to be salvaged and what three organelles does it involve

- entire process consumes what, releases what

- has affinity for CO2 and O2

- catalyzes O2, carbons in phosphoglycolate molecules must be salvaged

- involves chloroplats, peroxisome, and mitchodrian

- consumes O2 and releases CO2

- what does photorespiration not yield. 

- what does occur with

- when will plants photorespire (3)

- yields no ATP or NADPH

- occurs with CO2 fixation

- when CO2 is limited, dry hot conditions, plants growing close to each other

C4 pathway 

- what is first detectable molecule

- what enzyme does it use

- what is oxaloacetate reduced to 

-where does malate move to and what happens to it

- how is it seperated from the calvin cycle

-4c molecule oxaloacetate

- PEP carboxylase

- malate in mesophyll cells 

- moves to bundle sheath cells where it is decarboxylated and yields CO2 and pyruvate

- spatially 

C4 pathway cont.

-how many times does it evolve, ind/dep? 

-in Angiosperms, how many families, how many are monocots, how many eudicots? 

-evolves independantly, multiple times

-angiosperms include 19 families, 3 monocots, 16 eudicots

C4 Pathway cont. 

- what kind of anatomy? (german word)

- is it more efficient than C3 ? 

- how many ATP needed vs C3 

- what limits photorespiration 

- what is this pathway adapted to? 

- what does it have less of compared to other plants

- has kranz anatomy  (german for wreath)

- more efficient than C3 alone

- costs 5 ATP instead of 3 to fix one CO2 

- well adapted to high light, high temp, low soil moisture - DESERT

- less rubisco 

CAM plants: 

- what kind of metabolism do they have? (Dinosaurs)

- ind/dep evolutions in regards to succulents

- what pathways do they use?

- what kind of seperation do they have btwn pathways?

- able to fix CO2 in dark how?  

- Crassulacean acid metabolism

- evolved independantly 

- use both C3 and C4

- temporal seperation

- can fix using PEP carboxylase activity

CAM plants cont

- what do their cells have (2)

- when do they accumulate CO2? 

- describe stomata characteristics during day

- how does their water efficiency rate 

- more or less widespread than C4

- Must have large vacuoles to store malic acid, and chloroplasts

- depenedant on night time accumulation of CO2

- close stomata during day to reduce water loss.

- much greater than C3 or C4

- more widespread than C4, 23 families of angiosperms, mostly eudicot

Advantages/disadvantages of pathways:

what is more sensitive to cold? 

what is more sensitive to heat? 

what grows most slowly? 

- C4 more sensative than C3

- C3 more sensative than C4 or CAM

-CAM grow slowly because stomata closed 

When is carbon fixed? (during which process)

-where are carbohydrates used? (class of eater) 

-carbon is fixed during photosynthesis

-used by both autotrophs and heterotrophs

Greenhouse effect: 

-amount of carbon released by respiration and          

 combustion has exceeded the amount fixed by    

 photosynthesis

- increased since 1850, 3 billion metric tons a year