Plant Nutrition Flashcards
As plant grows what is the source of the raw materials that compose a plant?
water atmosphere and soil
sugars made by plants use
carbon and oxygen from the atmosphere
hydrogen from water
sugars made by photosynthesis is used in constructing
primarily carbohydrates
what is the direction of water movement through the plant?
from roots to leaves
What nutrient source contributes the most to the dry-weight biomass of these trees?
the atmosphere or air
root hairs greatly increase…
a roots absorptive surface
In what ways can water and solutes move through the root’s epidermis and cortex?
- through cell wall/plasma membrane
2. hydrophilic intercellular space
what is the casparian strip?
a selectively permeable plasma membrane that controls the substances that enter the vasculature of a plant
What cells form the xylem?
tracheid’s and vessel elements
xylem cells are both ______ and _____ when mature?
dead
hallow
describe tracheids..
long and thin with tapered ends
describe vessel elements..
thick and shorter w/ opening in the ends of cells
what pulls water up the xylem?
transpiration
xylem sap flows within the xylem and is pulled by
transpiration
sap movement is aided by _______ and ______
cohesion and adhesion
define transpiration
evaporative water loss
loss of water from the leaves causes negative pressure in the
mesophyll cells
define cohesion
forces that hold two of the same molecule together
define adhesion
forces that hold two different molecules together
water is a ______ molecule?
polar
50 gallons of water are used by one corn plant in a ______ and by one rainforest tree in a ____.
summer
day
What controls transpiration of a cell?
guard cells
When plants need CO2 guard cells?
swell and bow outward
To conserve H2O plants?
close the stomata
define turgor pressure
loss of K+ followed by the flow of water
What are some of the evolutionary adaptations of the stoma?
- placement
- number/ size
- when to open
define trichomes
leaf hairs
define hydrotropism
how roots search for water
What is the physical barrier in the root that regulates the flow of water to xylem via cell walls?
the casparian strip
what force is responsible for the cohesiveness of water?
the hydrogen bonding between water molecules