Exam 4 Flashcards
internal functioning of plants
plant physiology
the movement of molecules from an area of higher concentration to an area of lower concentration
diffusion
diffusion of water across a semipermeable membrane
osmosis
different substances diffuse at different rates through this
semipermeable membrane
a mixture in which things are dissolved evenly
solution
the substance things are dissolved in
solvent
the thing dissolved in the solvent
solute
a solution with a solute concentration higher than the cell’s (cell would lose water)
hyptertonic
a solution with a solute concentration lower than the cell’s (cell would absorb water)
hypotonic
a solution with a solute concentration equal to the cell’s
isotonic
when the plasma membrane presses tightly against a cell wall, the plant cell is…
turgid
when the plasma membrane is not tightly pressed against a cell wall, the plant cell is…
flaccid
when the membrane pulls away from the cell wall altogether, which over time may kill the cell , the plant cell is…
plasmolyzed
how is water potential calculated?
water potential = pressure potential + solute potential
what is water potential?
the total pressure driving water in one direction or another
water always moves from an area of __ water potential to an area of __ water potential
higher, lower
what are the three main processes that move water through plants?
1) root pressure
2) capillary action
3) cohesion tension theory
stimulation of movement of water up the roots and lower stim due to
root pressure
the movement of water up a narrow tube due to polar bonding is known as
capillary action
a chain of water molecules joined by hydrogen bonds is pulled up the plant by evaporation through the leaves, this is known as
cohesion tension theory
the evaporation of water out of a leaf which drives water movement through the mesophyll is known as
transpiration
air bubbles break the tension (the pull) of the water column in xylem vessels; the air bubble is referred to as
embolism
the loss of xylem function due to embolism is called
cavitation
in small plants, repairing cavitation involves __ forcing gas bubbles to dissolve
root pressure
in larger plants, __ may be imported into the __ to get more water flow out by osmosis
solute, xylem
building new __ is also a way of repairing cavitation
xylem
when guard cells are __, the stomatal pore is open
turgid
when guard cells are __ or __, they lose __ pressure and close the stomata
flaccid, plasmolyzed, turgor
conserving water by closing stomata means absorbing less __ and usually __ __
co2, less growth
to open, guard cells absorb __ from nearby __ cells, then water flows into guard cells by __ to create turgor pressure in the cell
k+, epidermal, osmosis
guard cells export __ to become flaccid and close the stomatal pore
k+
some plant species have epidermal pores at the tips of veins called
hydathodes
some aquatic plants and plants from moist environments excrete excess water through __ which is called __
hydathodes, guttation
macronutrients include…
N, P, K, Ca, S, and Mg
what is nitrogen needed for?
proteins
deficiency of this nutrient shows as chlorosis (yellowing in older leaves)
nitrogen
phosphorus is needed for
nucleic acids & ATP
deficiency of this nutrient shows as green leaves with purpling
phosphorus
potassium is needed for
stress tolerance
deficiency of this nutrient shows as yellowing of leaf margins with spots
potassium
calcium is needed for
cell division, leaf expansion, & membrane transport
deficiency of this nutrient shows as dying leaf margins, small leaves, dead terminal buds/meristems, small roots and blossom end rot (can be caused by lack of water)
calcium
magnesium is needed for
chlorophyll & enzyme activity
deficiency of this nutrient can show as interveinal chlorosis with some spots and leaves curling
magnesium
sulfer is needed for
amino acids
deficiency of the nutrient sulfer can show as
small, light green leaves with some dead spots
to live, cells must have
energy
what is energy
the capacity to do work (moving objects) or to produce heat
what is the law of conservation of energy?
in nature, energy is neither created nor destroyed but is transferred between forms
what is metabolism?
the sum of all the interrelated biochemical processes that take place in an organism
the breaking or forming of chemical bonds in metabolism is done by
proteins called enzymes
what are the types of metabolism?
anabolism
catabolism
secondary metabolism
the building of molecules by forming chemical bonds
anabolism
the breakdown of molecules by breaking chemical bonds
catabolism
reactions that produce compounds not strictly necessary for normal growth, like latex or nicotine
secondary metabolism
chemical energy from food is transferred into chemical energy in ATP
cellular respiration
what is the overall equation for cellular respiration?
C6H12O6 + 6 CO2 + 6 H2O + 38 ATP
respiration uses oxygen so it is a __ reaction
aerobic