lec 16 Flashcards
autotrophs
plants make their own food thru photosynthesis
hermaphrodites
male and female reproductive parts
photosynthesis
-responsible for O2
-removes CO2
how do plants grow
for growth, plants need to get more carbon through photosynthesis than they lose thru respiration
-carbon balance
primary productivity
how much plants grow
transpiration
when plants lose water and O2 through stomata
benefits of large leaf SA
good for harvesting light and CO2
costs of large leaf surface area
bad for overheating, water loss by transpiration through stomata
-bad in dry places
how do plants cope with overheating/water loss
most plants fix carbon by C3 photosynthesis
-rubisco is the enzyme that accepts CO2
-at high temps, rubisco often captures O2 instead of CO2, which’s bad for plants (photorespiration)
c4 photosynthesis
the enzyme PEP carboxylase first accepts CO2 reducing photosynthesis
CAM photosyn
plants close stomata during the day to reduce water loss, open stomata at night to let in CO2; photosynthesis still needs light, so they store CO2 as malate until daytime
plants with large leaves also combat overheating by
growing in shady habitats
evaporative cooling by opening stomata
plants with large leaves combat water loss by
closing stomata
…but that shuts off all gas exchange including CO2 input, so photosynthesis shuts down
-plant then stops growing and risks overheating and tissue damage
-tradeoff b/w water conservation and rapid growth
tropical trees
extensive shallow roots
-tropical rainforests have a shallow layer of nutrient-rich soil
-extensive, shallow roots are an adaptation to acquire scarce nutrients
nitrogen fixation
when bacteria can take nitrogen from air
how deciduous trees evade stress through behaviour
by dropping leaves during dry or cold seasons to reduce water stress and tissue damage
leaf shape
influences gas exchange through laminar VS turbulent air flow
laminar
Definition: A smooth, orderly flow of fluid where fluid particles move in parallel layers without mixing between them
turbulent
A chaotic, irregular flow of fluid characterized by eddies, swirls, and vortices, leading to mixing between fluid layers
-layers cross
-better for gas exchange
more laminar flow
less cooling
more turbulence
better cooling
recursive digresson
convective cooling aided by turbulence
could metaphorically describe how layers of cooling processes interact or how analyses of these processes might branch into interconnected factors
Convective cooling involves heat transfer from a surface to a fluid (like air or water) due to the movement of the fluid.
The recursive aspect can emerge in:
Flow Patterns:
For turbulent convection, eddies or swirls create smaller, nested eddies, each contributing to heat transfer. These interactions could be seen as “recursive digressions” of the main flow pattern.
epiphytes
Epiphytes are plants that grow on other plants for physical support but are not parasitic—they do not take nutrients from their host plant
Instead, they derive moisture and nutrients from the air, rain, and debris that collects around them
Epiphytes are commonly found in tropical and subtropical regions, where their adaptations help them thrive in competitive ecosystems like rainforests.
epiphytes grow on trees, so they aren’t able to put…
their roots into the soil, leading to water stress and nutrient shortages
