plant Transport Flashcards
under what 2 conditions does the highest rate of transpiration occur
sunny
high temperature
give an account for the movement of water in plants
water pushes into root hairs by osmosis
cohesion- water molecules stick to eachother by H bonds, forming a continuous chain of water molecules
adhesion- water molecules cling to walls of xylem
what is the advantage of having the stomata on the underside of the leaf
prevents excess transpiration
what controls the opening and closing of the stomata
guard cells
high rates of transpiration can have negative effects name one
wilting
explain how water enters the root hairs and then passes onto xylem
root hair by osmosis and then it diffuses into the ground tissue and into the xylem
name the 2 scientists who proposed the cohesion tension model
dixon and joly
what force is the cohesion tension model moving against
gravity
how do plants respond to high levels of transpiration
close its stomata
give 2 features which facilitate the upward movement of water in the plant
xylem are narrow, have pits and lignin
what is the function of ground tissue?
the site of chemical reactions
what is the function of dermal tissue?
protection
what is the function of meristematic tissue
areas of growth
through what process do minerals enter the root
active transport
why are strong forces of attraction between water molecules necessary?
to form a continuous chain of water molecules
state 3 ways the leaf is adapted for photosynthesis
contains lots of chloroplasts
has stomata
its very thin
give 2 structural differences between phloem and xylem
phloem have companion cells
phloem doesn’t have lignin
xylem doesnt have have companion cells
xylem has lignin
name the type of division that occurs in meristematic tissue
mitosis
name 3 substances and products of metabolism which pass through the stomata
oxygen
CO2
water
which gas influences the diameter of the stomata
CO2
describe the principle features of the cohesion tension model
water molecules stick together
this forms a chain of water molecules
chain is pulled upwards through xylem due to transpiration
water molecules stick to walls of the xylem
