Transport (plants)

• Phloem

  Transports sucrose and amino acids
• Translocation

  The movement of sucrose and amino acids up and down the plant
• Substances are made (the sources)

  Moved to where they are used or stored (the sinks)
• The xylem carries water and mineral ions from the root hairs upwards t the leaves by transpiration the vessel sells are dead bc of the walls impregnated by waterproof strengthening materials so ithe insides die. Energy comes from evaporation of water from stomata and it has thick cell walls because of xylem vessels
• The phloem carries sucrose and other organic material from the leaves to the sinks the direction is up and down and this process is by translocation. The vessel cells are alive because the materials need to be pumped up and down. Energy comes from respiration in mitoch forming ATP. The cell walls are thin because of the phloem sieve tubes
• The xylem is a hollow tube and it’s made from a chemical called lignin
• Xylem structure Is it had no cytoplasms, it’s impermeable to water and it contains lignin
• Root cells have no chloroplast because they’re underground so no photosynthesis
• Water is absorbed into the plant by osmosis via the root hair cells. They are adapted for taking up water and mineral ions by having a large s area to increase absorption rate
• Transpiration is the evaporation of water from the aerial parts of the plan. The roots take up water from the solid, water is drawn up the stem to the leaves. Veins carry water into leaves, water evaporates from the leaves
• Factors that affect the rate of transpiration are humidity, temperature, light intensity and wind speed
• Humidity affects the rate of transpiration as if there is high humidity then less water will be lost through transpiration
• Temperature affects the rate of transpiration as warmer air holds more moisture than cooler air. If its hotter then more water will be lost through transpiration
• Light intensity affects the rate of transpiration as plants lose more water when exposed to bright sunlight
• Temperature affects the rate of transpiration as higher temperatures mean more energy available for evaporation
• Wind speed affects the rate of transpiration as faster winds cause greater air movement over the surface of the leaf which increases the rate of evaporation
• if wind is increased, water is removed
• If half of the leaves are removed, less surface area
• If light intensity is reduced, stomata closes
• For leafy shoot test, cut the stem under water, make air tight, dry the leavest dry the leaves, bubbles are introduced, measure distance bubble moves
• the apparatus used for the leafy shoot test is a potometer
• in the leafy shoot the concentration gradient and molecule speed need to

  be controlled
• Transpiration helps plants take in water and minerals and it helps them cool down