5. Support and Transport systems in plants Flashcards
Name the 2 types of seed plants
Gymnosperms and Angiosperms
What is an Gymnosperm?
Non-flowering plant with naked seeds on cones.
Give 2 examples of Gymnosperms.
cycads, pine trees
What is a Angiosperm?
Flowering plant with seeds in fruit.
Give 2 examples of Angiosperms.
Sunflowers, fruit trees
What are the 2 classes of Angiosperms?
Monocotyledon and Dicotyledon
What are the 3 support tissues in plants?
Collenchyma, Sclerenchyma and Xylem
What are the 2 transport tissues in plants?
Xylem and Phloem
Provide the defintion of Transpiration
Loss of water in the form of water vapour from the aerial parts of a plant.
Name the 2 types of Transpiration.
Stomatal and Cuticular
Describe the relationship between the structure of a leaf and water loss.
- Thorns and hairs to limit transpiration.
- Smaller leaves means less surface area for evaporation.
- Leaves with sunken stomata will limit transpiration.
What do the Guard cells do?
Control rate of transpiration by closing and opening the stomata.
What do the Cuticles do?
Waxy layer to reduce cuticular transpiration.
Explain Stomatal mechanism during the day.
- Photosynthesis in guard cells of stomata.
- Glucose collects in guard cells.
- Water into guard cells from surrounding epidermis cells thorugh osmosis.
- Guard cells bend outwards because of thin outer wall and thicker inner wall.
- Stomatal pore opens
- Water diffuses out of leaf
Explain Stomatal mechanism during the night.
- No photosynthesis
- Reserve glucose used up.
- Water moves into epidermal cells through osmosis.
- Guard cells bend inwards.
- Stomatal pore closes
- Less water diffuses out of leaf.
Name the 4 external factors affecting the rate of transpiration.
- High temp increases rate
- Higher light intensity increases rate
- High humidity decreases rate
- Wind decreases rate
Name the instrument used to measure the rate of transpiration.
Potometer
Explain the uptake of water and minerals by the roots
- Water potential in soil is higher than of cell sap in vacoules of root hair.
- Water molecules move by osmosis through permeable cell wall, selectively permeable cell membrane and cytoplasm through selectively permeable tonoplast into vacoule of root hair.
-Vacuole swells and pressure in root hair increases. - Turgor pressure
Explain the movement of water from root hair to xylem of root.
- Water potential in root hair is higher than in adjacent parenchyma cells in cortex of root.
- Water moves to xylem of root from cell to cell by osmosis and through cell walls and intercellular air spaces between cells by diffusion.
- Water can’t pass endodermis cell walls
- Water moves through cells of endodermis through pericycle to root xylem.
Name the 3 forces responsible for the upward movement of water.
- Transpirational pull
- Root pressure
- Capillarity
What is Transpirational pull?
Water lost through leaves by transpiration is replaced by absorbed water from soil through root hairs.
What is Root pressure?
Pressure that develops as a result of the absorption of water into root by osmosis.
What is Capillarity?
Ability of water molecules to rise up a very narrow tube.
Name the 2 forces in Capillarity.
Adhesion and Cohesion
What is Adhesion force?
Forces of attraction between water molecules and molecules of the xylem.
What is Cohesion force?
Attraction forces between water molecules.
Explain the translocation of manufactured food from leaves to other parts of the plant.
- Translocated inside sieve tubes inside of phloem.
- Companion cells assist in functioning of sieve tubes.
Provide the definition of Root hair.
Unicellular epidermal outgrowths that increase absorption of root.
Provide the definition of Casparian Strips.
Waxy strips in lateral walls of endodermis.
