Transport (plant) Flashcards
Describe the role of phloem in flowering plants.
Phloem transports sucrose and amino acids from photosynthesizing leaves to nonphotosynthesizing regions in the roots and stem
How does the structure of the phloem differ from the xylem?
- Phloem cells are living and not hollow
- xylem cells are dead and form hollow tubes.
Explain the process of water and mineral transport in the xylem.
Xylem vessels transport water and minerals from roots to stems and leaves through hollow tubes strengthened by lignin.
How are root hair cells adapted for water and mineral uptake?
- They absorb mineral ions by active transport, against the concentration gradient.
- Root hair cells are adapted for taking up water and mineral ions by having a large surface area to increase the rate of absorption.
- They also contain lots of mitochondria, which release energy from glucose during respiration in order to provide the energy needed for active transport.
Define transpiration.
Transpiration is the evaporation of water from above-ground parts of a plant, including leaves, stem, and flowers
How does humidity affect the rate of transpiration?
Higher humidity reduces the concentration gradient, slowing the transpiration rate.
Describe the effect of temperature on transpiration.
Higher temperatures increase the rate of transpiration due to increased evaporation
Explain the relationship between light intensity and transpiration.
Higher light intensity leads to more open stomata, increasing transpiration until all stomata are open.
How does wind speed affect transpiration?
Higher wind speed increases the diffusion gradient, increasing the transpiration rate.
What is a practical method to investigate the role of environmental factors in transpiration?
Use a photometer to measure the movement of an air bubble in a capillary tube under different environmental conditions.
Discuss the role of xylem and phloem in the transport system of a flowering plant.
Xylem transports water and minerals from roots to other plant parts, while phloem transports sucrose and amino acids from leaves to non-photosynthesizing regions, enabling bidirectional movement.
Describe how water moves from roots to the leaves
- By transpiration in xylem
It was important to use the same plant cutting each time to make these experiments fair. Explain why.
different plants have different sizes
Describe the process of transpiration
- Once inside the root cells, it can pass into the xylem vessels to be taken up the stem to the leaves.
- However, if the leaf is photosynthesizing then water is lost through the open stomata.
- This process is called transpiration.
The plant used in this investigation has very few stomata on the upper surface of the leaf. Explain why this is an advantage for the leaf.
- Less water lost
- It does not wilt
