1 / 13

Resource Acquisition and Transport in Vascular Plants

Resource Acquisition and Transport in Vascular Plants. Resource acquisition and transport. Transport review. Passive transport – no energy required, ex. diffusion Active transport – energy required Transport proteins required, ex – proton pump

alverson
Download Presentation

Resource Acquisition and Transport in Vascular Plants

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Resource Acquisition and Transport in Vascular Plants

  2. Resource acquisition and transport

  3. Transport review • Passive transport – no energy required, • ex. diffusion • Active transport – energy required • Transport proteins required, ex – proton pump • Uses energy from ATP to pump H+ across membrane • Cotransport– coupling of the steep gradient of one solute(H+) with a solute like sucrose • Drop in potential energy by H+ pays for transport of sucrose.

  4. Water potential (potential grid problems) • Osmosis – movement of water across cell membrane via aquaporins • Water moves from area of high water potential to low potential • Water potential includes the effects of solute concentration and physical pressure.

  5. Transpiration • Loss of water vapor from the leaves • Water and minerals are transported to rest of plant via bulk flow • Bulk flow is the movement of liquids in response to a pressure gradient • Rate of transpiration is regulated by stomata

  6. Stomata • Pore in leaf epidermis with guard cells on each side. • Water enters guard cells, following K+, turgor pressure increases, stoma opens and vise versa • Stomata open and close in respond to environmental signals

  7. Cohesion-tension hypothesis • Transpiration provides the pull for the ascent of water. • Water is lost due to lower water potential of the air • Cohesion of water molecules via hydrogen bonds plus adhesion of water to plant cell walls form a water column.

  8. Organic nutrient transport • Girdling – removing bark form tree, accumulation of sugar • Pressure flow model – 29.22 • Sugar enters the sieve tubes (active transport) and creates positive pressure, phloem begins to flow • Roots are a sink – provide place for sugar to be used for cellular activities (respiration) • Source to sink – leaves to roots or any place that needs sugar (new leaves…)

  9. Soil and Plant Nutrition • 95% of plant’s dry weight (biomass) is carbon, hydrogen, and oxygen (carbohydrates, CO2 and water) • Minerals – provide proteins and nucleic acids • Essential nutrients – has role, no substitute, and a deficiency results in death. • Macro and micronutrients according to concentration • Beneficial nutrients – required or enhances growth

  10. Mutualistic relationships • Nitrogen-fixing bacteria – root nodules of legume plants • Fix atmospheric nitrogen into a form that plants can use, plants provide food to bacteria • Mycorrhizae – plant roots and fungi, plants give fungus food, fungus increases surface area for water uptake and minerals

  11. Symbiotic relationships that arenot mutualistic • Parasitic plants (dodder), does not undergo photosynthesis, needs other plants for nutrients • Epiphytes – grown on surface of other plants instead of soil, not parasitic, ex. orchids • Carnivorous – photosynthetic but get some nitrogen and minerals from small animals

More Related