Photosynthesis

EMR

electromagnetic radiation

pigments

chemicals that are sensitive to light

chlorophyll a

most common pigment, absorbs blue/purple and red/yellow and reflects green. temperature sensitive, in fall it starts to break down and let other pigments show

englemann experiment

purpose is to see what colors are used in photosynthesis

chloroplast

organelle in the plant cell where light is converted to usable energy, contains two membranes and is filled with a fluid called the stroma, contain it’s own DNA

endosymbiotic theory

how chloroplast and mitochondria have their own DNA, used to be their own free-living organism

thylakoid

where photosynthesis happens, is very folded, the thylakoid membrane is where ‘light’ reactions occur

what are light rxns

light dependent rxns, cyclic and non cyclic pathways

what are dark rxns

light independent rxns, calvin cycle

what are the non-cyclic pathways reactants and products

reactants - H2O, NADP+, ADP

products - O2, NADPH, ATP

photolysis

water breaking using light

photophosphorylation

using light to attach phosphate to ADP

what are the cyclic pathways reactants and products

reactants - ADP

products - ATP

why does the plant need NADPH and ATP

to make sugar for cellulose and energy storage

what is the calvin cycle

in the stroma, its when CO2 come into the leaf and gets turned into sugar, energy contained in ATP + NADPH are what drives the this process

what are the reactants and products of the calvin cycle

reactants - CO2, ATP, NADPH

products - NADP+ ADP and sugars

what does NADP+ availability determine

if a plant completes the cyclic or non-cyclic process

where does calvin cycle occur in C3 plants

Calvin cycle occurs in a plant tissue of a leaf called the mesophyll

what are the stoma

tiny holes in bottom of leaves, open to allow CO2 to get in and O2 to get out, close to prevent H2O from getting out, without being open CO2 can’t get out therefore calvin cycle can’t occur and O2 can’t get out, being open allows H2O out dehydrating plant

RUBISCO

calvin cycle enzyme, job is to fix CO2 but can get confused and fix O2 in process called photorespiration (bad) which wastes ADP + NADP+

in C3 plants where do the light and dark rxns occur

spongy mesophyll cell

in C4 plants where do light and dark rxns occur

light - mesophyll cell

dark - bundle sheath cell

what is the evolution seen in C4 plants

spatial difference where photosynthesis occurs to prevent photorespiration

CAM plant evolution

temperal difference

temperal difference

when stoma open at night to let CO2 in to store it and let O2 out. close during the day to prevent H2O escaping but can still make sugar due to stored CO2

autotrophs

make their own food

photoautotrophs

make their own foods with sunlight

what are most animals/fungi/protists

heterotrops

chemoautotrophs

first cells (bacteria), make own food with chemical. evolution occured and energy from sun was utilized, cyclic pathways developed first so there was no O2 in the air