Plant Nutrition and transport - Fayetteville State …faculty.uncfsu.edu/ssalek/Biol130/CH...
Transcript of Plant Nutrition and transport - Fayetteville State …faculty.uncfsu.edu/ssalek/Biol130/CH...
Real Quiz!
• Closed book, 10 minutes, 10 points
Draw a GENERAL diagram that describes how a plant undergoes alternation of generations. In your diagram include all the different phases that the plants go through and the processes that lead from one phase to another. Indicate which phases have the full chromosome number, and which have half the chromosome number.
Uptake and transport of plant nutrients
• Co2 enters plants through the leaves• Water, minerals and some O2 enters
through from the soil through the roots• All other materials are produced through
mixtures of these• Energy is obtained from the respiration of
sugars. Leaves produce O2 for this , roots absorb it from the soil
Solute uptake in the roots• Roots have large surface area• Mycorrhizal fungal interactions supply
nutrients and water to the plant• Substances enter roots both
intracellularlly and extracellularly, control over substances occurs at the cell membrane
• Intracellular (root hair membrane-plasmodesmata-cortex cells, endodermal cells- xylem)
• Extracellular (porous cell walls,around casparian strips, to xylem
Properties of waterWater molecules stick to one Another (cohesion) and other s(adhesion)
Water is a polar molecule
Fig 2.9
Fig 2.10
Transpiration
• Water – cohesion, diffusion, osmosis• How do plants lift water from the roots to
the leaves• Root cell membranes pump solutes into the
xylem, then water follows• Transpiration – adhesion-cohesion
– Evaporation of water from leaves thru stomata– Cohesion of water molecules in the xylem– Adhesion of water to cellulose
Sugar transport
• Sugars are made at “sugar sources”• Sugars travel to and are used at
“sugar sinks”• Osmosis is responsible for
generating pressure differences that move the sugar.
• Proof ! –Aphids!