Gas Exchange In Flowering Plants

-Air spaces increase surface area to volume ratio for faster rate of gas diffusion -Stoma open to allow diffusion of CO2 into leaf during photosynthesis and oxygen and water vapor out leaves -Leaves thin to provide short diffusion distance for rapid diffusion of gases in and out of leaf -Leaves flat which provide large surface area for absorption of carbon dioxide during photosynthesis -Guard cell around stomata control opening and closure of stomata to control gas diffusion in and out of leaves

Respiration take place all time so oxygen taken by respiring cells and carbon dioxide produced as waste product During day time ligh present allow photosynthesis to occur so carbon dioxide takin in and oxygen taken out During day rate of photosynthesis higher than rate of respiration carbon dioxide diffuse into leaf and oxygen diffuses out

No light present so no photosynthesis will occur Oxygen diffise into leaf and carbon dioxide diffuse out

• In light water enter gaurd cell by osmosis from surrondings epidermis cells • Guard cells become turgid and swell • Thick inner walls will split and guard cell will bend outward open stomta • In dark dark gaurd cells lose water • Guard cells become flaccid • Thick inner wall stick together close stomata

Co2 use in photosynthesis and produce by respiration where oxygen used in respiration and produced In photosynthesis