16. Physiological ecology: plants Flashcards
Photosynthesis
CO2 + H2O ( light)–> Carbs + O2
Respiration _ _ _ energy
CO2 + H2O <–(ATP energy) Carbs + O2
Sessile
of an organism, e.g. a barnacle fixed in one place; immobile
Autotrophic
they make their own food through photosynthesis
Net primary productivity (NPP)
C gained via photosynthesis – C lost via respiration = NPP
Transpire
they lose water through stomata (singular stoma)
Benefits of large leaf surface area
good for harvesting light, CO2
Costs of large leaf surface area
bad for overheating, water loss by transpiration through stomata
C3 photosynthesis (photorespiration)
Plants which use only the Calvin cycle for fixing the carbon dioxide from the air
C4 photosynthesis (adaptation for high temperature environments)
the enzyme PEP carboxylase first accepts CO2, reducing photorespiration
CAM photosynthesis (adaptation for high temperature environments)
plants close stomata during the day to reduce water loss, open stomata at night to let in CO 2; photosynthesis still needs light, so they store CO2 as malate until daytime
Deciduous habit
dropping leaves during dry or cold seasons reduces water stress and tissue damage
More turbulent flow=
better for cooling leaves
Epiphytes
plants that grow on other plants (often have water stress because they aren’t able to put their roots into the soil, leading to water stress and nutrient shortages)
To solve this problem, they have evolved a ‘tank’ of water
Recursive digression
convective cooling aided by turbulence
