Plant Transport Systems - RAB Quarter 2 Notes PDF

RAB QUARTER 2 - by Gia Angela M. Valenzuela and Craig Nathaniel F. Climacosa PLANT TRANSPORT SYSTEMS - November 26, 2024 XYLEM Carries water and nutrients throughout the entire plant Tracheids - is a part of the xylem with pointed ends and thick walls with pi...

RAB QUARTER 2 - by Gia Angela M. Valenzuela and Craig Nathaniel F. Climacosa PLANT TRANSPORT SYSTEMS - November 26, 2024 XYLEM Carries water and nutrients throughout the entire plant Tracheids - is a part of the xylem with pointed ends and thick walls with piths that connect them to cells Vessel elements - is a part of the xylem that is wider, shorter, thin walled, and less tapered Cohesion - Tension Theory This states that the water moves up the xylem of a vascular plant due to root pressure, transpiration, and the adhesive and cohesive properties of water. ○ Cohesion - the property of water to bond with other water molecules ○ Adhesion - the property of water to bond with the molecules of other substances ○ Transpiration - when plants lose water through evaporation in their leaves PHLOEM Carries sugar and other organic materials throughout the entire plant Contains living cells that transport sugars and amino acids to other plant parts Sieve plate - is a part of the phloem that turns the nutrients into fine pieces as they pass through Phloem parenchyma - is a part of the phloem that offers protection and flexibility for the transportation system Pressure Flow Hypothesis This states that the materials from the phloem move from the source to sink cells.  ○ Source cells - this is where the organic materials come from, usually these are found in leaves that contain photosynthetic tissues ○ Sink cells - this where the materials are utilized, usually these are found in the growing roots or developing fruits that use energy from cell respiration ○ Translocation - states the movement of organic materials from source to sink Other related terms: Lignin - This is an organic substance that composes 25% of the cell wall. It is composed of cellulose and is hard to process due to its rigid property. Hence, it may serve as the backbone or support for the plant, and also, as the protector of the xylem and phloem. Cambium - This separates the xylem and phloem SYMPLAST & APOPLAST Symplastic - describes the movement of water from cell to cell Apoplastic - describes the movement of water in extracellular spaces *This is important because in some situations such as when plants absorb toxins, these movements give people time to save some parts of the plant, and therefore, may serve as a filter.