biolec 4
why is the way plant deal with the environmental conditions different to animals.
plants are sessile they cant move which makes things alot differet as it limits their behavior responses to changes in environent as they cant relocate is the temperature or seasons change. they have different stress induced mechanisms.
they are also prducers and make their own food unlike animals who have to consider food sources as well as their environemnt and sometimes this leads to tradeoffs in animals.
plants need only few things like co2 and water and nutrients for photosynthesis and to survivle
what is the NPP
NPP stands for net primary productivity. which is the amount of carbon gained via photosynthesis - the c used via respiration.
what are the plant adaptations for photosythesis and how is it good or bad for them
the leafes have large sa/v ratio : PRO to capture as much sunlight CON is that this can lead to rapid water loss by transpiration, and hecne cause overheating.
the leaves have many stomata PRO this means that they can take in alot of co2 for photosynthesis, but this means alot of water as h2o can also be lost via transpiration.
why is overheating bad and how is it caused and how do plants adapt to it
some plants at higher temperatures ( under some conditions this causes a phenominon called photorespiration where rubisco takes in o2 instead of co2 and so there is ultimately less photosynthesis) but plants have develpoed c4 pathways which evovles another enxymes not Rubisco which is PEP carboylase which only accepts co2 reducing photorespiration. and also CAM photosythesis which is that stomatas are closed during the day to converse water but that means they take in co2 during the night and store it as malate until the day where light is absorbed and photosynthesis happens.
what is the trade off in plants
one bif tradeoff is that the plants reduce wwaterloss by closing stomata but this means that they cant take in co2 so cuases stunted growth in the plants
what is palo verde ans what does this plant show
this is an example of a desert plant as it has something called 'green stick' which means that it has photosytheitc barks and stems and the leaves do not need to photosynthsise and so can lose them to prevent overheating anf water loss.
also have microphyly which is very small leaves
what is microphylly
small leaves
phenomenon of shallow roots
both desert plants and tropical plants have this but for different reasons. the desert plants have shallow roots to find water easily as it doesnt rain to much so when it does need to capture before it gets lost. tropical bec nutrient rich soils is at the top layers
root forrages
plants look for nitrogen-fixing bacteria . and grow accordingly
behavioral adaptations of plants
the examples are dropping leaves during dry and cold seasons and plasticity regarding laminar and turbulance air flow. the lamiar increases hot effect and less heat loss as the layer are removed one by one and that takes very long compared to turbulance flow
can troical trees and plants also face ater shortages
they can if they are epiphytes bec they dont have roots into the ground but on other plants and they take up water and nutrients from the suurounding eg when it rains. but they can harm their host plant that they are on by ading weight and casuong them to break or competing for light