week 8 Flashcards
(39 cards)
Multicellular eukaryotes are inherited from their
charophyte ancestor.
what is a charophyte
taxon of green algae
A Food storage molecule is called
amylose starch
where are shoot systems located on the plant
root system functions
Usually grow underground but not always
Anchors plants support it upright.
Absorb water and dissolved minerals from soil. Towards shoot.
Store carbohydrates.
Unique features:
l
Lipid bilayer
primary cell wall, different physical properties give it a bit of different functions.
Rigid but flexible
Vacuole:
Used for storage and maintain turgor pressure against cell wall.
What is Transpiration,
the loss of water vapour from the leaves creates a negative pressuretension:
cohesion
the way water molecules stick together. Water molecules stick to itself together itself and water droplets. Cohesion fights the gravity pull and makes molecules stick together.
Adhesion-
Sticks to other things. For example water would stick in a container more than alcohol would, water molecules pulls on to the side of a chamber through the process of pulling themselves up.
why does water move up through tracheids
Water moves through tracheids upwards because they have thin and adhesive properties
are vessel members more broader or thinner
Vessel members are much more broader depend more on cohesion to transport water.
continuous movement of water occurs which refers to
TACT
The root pressure:
Positive pressure in roots that forces xylem sap upward, occurs in high humidity or low light and allows movement of water up short distances.
Guard cells can open and close, what happens.
when they are closed they are flaccid. In contrast when they open they are turgid.
when guard cells open they..
Guard cells when the open, activity remove protons, which makes. A negative charge.
when guard cells close the
The roots and leaves which binds to receptors on guard cells, stopping H+ pumping and opening chlorine channels.
Sinks are
where organic substances are unloaded from the phloem
Water will always move to where it is
rarer
apoplastic pathway
water does not cross cell membrane, diffuses through nonliving regions including cell walls and air spaces.
symplastic pathway:
water crosses membrane, often uses plasmodesmata, diffuses through cytoplasm, and moves in a sort of a straight pathway
Transmembrane pathway:
water crosses plasma membranes and tonoplasts. molecules that move back and forth.
What is the Caspian strip
band-like thickening in the center of the root endodermis of vascular plants
O-horizon
scattered litter such as leaves
