Chapter 26: Nutrition And Transport In Plants Flashcards
Active transport
Plants absorb minerals out of the soil by active transport using transport proteins
Van Helmont
Willow tree experiment
Macronutrients
CHPMgONK
Carbon, hydrogen, oxygen, phosphorous, potassium, nitrogen, magnesium
Micronutrients
Zn, cu, fe, mn
Water movement through the plant:
Water and minerals can move laterally
Water movement through the plant:
From cell to cell through membranes
Plants can control water movement and the casparian strip insures taut the control occurs
Facilitated diffusion
No cell energy required
Aquaporins
Proteins that extract water
Symplastic movement
Water moving from cell to cell through a tube. No control is possible
Plasmodesmata
Little tiny ports inside of cell transport water
Apoplastic movement
Water moving through the cell walls
Mineral uptake-
- N2 fixing bacteria
2. Mycorrhizae- fungus that increases the surface of roots for water and mineral uptake
Tracheids
Taper and overlap with pits in between
Vessel elements
Short, wide tubes arranged in a series- some have perforated walls some have these walls absent
Companion cells
Associated with non nucleated sieve tube offer chemical support- connected by plasmodesmata
When does water entering roots through osmosis generally occur?
Night
to get to vascular cylinder
Dermal layer, cortex cells, casparian strip, endodermis, xylem cells
Guttation
Results from root pressure in some plants- seen by drops of water at the margin of leaves
Effects on transpiration
- Hear- evaporation doubles for every 10 degree Celsius
- Humidity- when low- greater evaporation
- Wind- more evaporation when strong winds
- Guard cells most influenced by above factors
Turgid guard cells
Bow our to open the stomata
Protons are carried by a
Proton pump out of the guard cells. K+ ions into guard cells
Factors that affect movemet of k:
- Availability of water- when low, stomata close before wilting occurs
- Abscisic acid- hormones causes the uptake of k+ followed by water, cause to open up
- High levels of co2 in the leave cause stomata to close
- High temps cause stomata to close
- Blue light stimulates the movement of the proton pump
Circadian rhythm
Open in morning and close and dusk
Closed stomata
Conserves water but no co2 can enter and no photosynthesis