Theme 4 Homeostasis In Land Plants Part 2 Flashcards
What can we do to manipulate plants to maximize nitrogen uptake
Make them make their own nitrates from atmospheric nitrogen
Make them all have symbiotic relationship with nitrogen fixing bacteria
What is hydroponics
Analyzing the ashes from plants
What is a hydroponic culture
Growing plants in a solution and removing one nutrient at a time and seeing the affect on the plants growth
Seeing what elements are essential for the plant nutrition
What does and element need to be essential
Need to be required for growth and reproduction
Can’t be replaced/substituted
Needs to play one or more roles in metabolism
What is chlorosis
What is the result
The yellowing of the leaves in a plant due to lacking chlorophyll
Doesn’t do photosynthesis as efficiently
What soil made of
Contains soil-mineral particles, compounds, ions, decomposing organics, water, air, organisms
The soil particles have varying sizes (clay particles, silt, sand) in increasing order
What is important about soil particles
The amount of the particles determines the properties of the soil
Ex. Water availability
Mineral availability
What is humus
Decomposing organics near top of the soil that hold water and nutrients that seep down into soil
Increases water availability
What is soil solution
Everything available to the plant after water has drained through the soil by gravity
This water solution clings to soil particles and fills the pores between the particles,
has negative charge from clay and humus which attracts water molecules
Mostly in the upper soil layer
What is sandy soil
It’s soil that is looser and holds less water than clay soils
Everything entering the root surface has to be
Dissolved in water (soil solution)
What is present in the soil solution
What happens if you over water
Both anions and cations but they aren’t equally available to the plant
The anions get washed out so they’re less available,
also since soil is negatively charged due to the clay in the soil solution, the anions are repelled and cations are attracted to the soil
How do mineral in soil solution enter the plant roots
Mineral and water are taken up by Passive transport
They’re selectively adsorbed the roots through ion specific transport proteins
What is an adaptation which helps to uptake the limiting mineral (anions)
The roots go deeper and deeper into soil to reach the repelled anions
What is cation exchange
The mineral cations (mg ca k) are adsorbed (stuck to) the negative soul particles
Through cation exchange, the mineral cation on the soil gets kicked off and replaced by h+ . Because ph changes very close to roots
One way is The respiration of root releases co2 which reacted with water to make carbonic acid which dissociate to h+.
Another way is proton pumping of h+ which is an active proccess
What is leaching
When anions are washed away easily by excess water
if ph of soil is 4 (low) what mineral are not available and what minerals are leached out
It’s acidic
The anions are bound to the soil through attraction
The cations are freely floating (available) but they can be leached out
How can soil turn acidic
Due to acid rain,
Cations are leached out easily
Alkaline soils
Anions leach out easily
Acidic soils
Cations leach out easily
What does iron need to be before it can be taken up by plant
What does this
Fe3+ needs to turn into Fe2+
The protien FRO reduceces ferric to ferrous
What is passive transport
no metabolic energy required
The substance moves down a concentration gradient (has to do with membrane potential)
Moves from more to less substance
Is simple diffusion
What ions do simple diffusion
What is facilitated diffusion
H2O o2 co2
Type of simple diffusion: Go though Transport protiens to help move through membrane (ion carriers, channel proteins). This also requires no nrg
What is active transport
Needs atp
The substance moves against the concentration gradient (from less to more)
Need transport proteins (channels) the use energy to move the stuff (ex. H pump)
