Biology - Plant Gas Exchange

describe how the spongy mesophyll is adapted for gas exchange

• has a lot of air spaces to allow gases to diffuse faster

• increases SA to vol ratio

describe how guard cells are adapted for gas exchange

• sunlight / water stimulates the guard cells to open the stomata and they become turgid

• lack of sunlight / water stimulates the guard cells to close the stomata and they become flacid

describe how stomata are adapted for gas exchange

• gas exchange and transpiration occur at the stomata

• stomata is open during the day (light) and closed during the night (no light)

describe how thin leaves are adapted for gas exchange

• shorter diffusion distance for CO2 to diffuse in and O2 to diffuse out

describe how the leave’s flattened shape is adapted for gas exchange

• increased surface area

• allows for more absorption of light and CO2

photosynthesis equation

• carbon dioxide + water → glucose + oxygen

respiration equation

glucose + oxygen → carbon dioxide + water + energy

what is the path of water through the plant

root hair cell → root cortex cells → xylem → leaf mesophyll cells