Plant Transport and Coordination Flashcards
The transport system in plants enables two things, what are they?
The transport system in plants enables leaves to receive water for photosynthesis and mineral ions needed to convert the products of photosynthesis into useful substances.
What type of walls does the xylem have?
Thick cell walls
For transport in plants, what are the dead cells that contain no cytoplasm are completely hollow and arranged end to end?
Xylem
What does the xylem transport?
The xylem transports water and mineral irons from the roots to the leaves.
For transport in plants what are nitrate ions needed for?
Nitrate irons are needed to make amino acid‘s and proteins
For transport in plants, what are magnesium ions need it for?
Magnesium ions are needed to make chlorophyll
For transport in plants, what type of cells are the xylem and the phloem made of?
The xylem is made of dead cells, and the phloem from living cells
For transport in plants, how is the phloem composed?
Tubes are formed by cells arranged end to end, but have cell walls made of Celulose.
For transport in plants, what is the sugar made in photosynthesis converted to?
Sucrose (another sugar)
What does the phloem transport, and to where in the plant?
The phloem transports sucrose and amino acids from the leaves where they are made, to the growing points.
Moving sucrose and amino acids around the plant is done by the Phloem. What is this called?
Translocation
Label this diagram of a xylem and phloem
How do plants take in water from the soil?
They take in water from the soil through their roots, this is the main site of water absorption.
Describe the roots of a plant.
The roots of a plant have hair like structures that greatly increase the surface area of the root epidermis, increasing the rate of diffusion.
What is the function of a root hair?
The function of a route is to absorb water and minerals from the soil. Each hair is a single specialised cells of the root epidermis
Through what process does the water enter the cells of the root hair?
Osmosis
Water is carried by the xylem vessels to where?
Water is carried by xylem vessels to all parts of the plant.
What is the word that means the evaporation of water from the surface of a plant?
Transpiration
Transpiration causes water to be pulled up the xylem in the stem and roots, in a continuous flow. What is this known as?
Transpiration stream
What are the three functions of the transpiration stream?
1) To carry mineral ions to the leaves for the synthesis of amino acids and chlorophyll
2) To keep pressure high in leaf cells, holding the leaves up
3) Evaporation cools the leaves
For transpiration, where does most water pass out of the leaves as water vapour?
Stomata
What happens to transpiration when the temperature increases?
On a hot day water evaporates more quickly from the leaves of a plant. Transpiration therefore increase as temperature increases.
How is transpiration affected with a change in humidity?
Very humid air contains a great deal of water vapour. Therefore there is a slower rate of diffusion, and a lower concentration gradient. So more humidity slows down transpiration.
How does wind speed change the rate of transpiration?
In moving air / high wind speeds, the water vapour will be swept away from the leaf as fast as it diffuses out. This will speed up transpiration. Transpiration therefore increases as wind speed increases.
How does light intensity change the rate of transpiration?
Light itself does not affect evaporation, but in daylight the stomata of leaves are open to supply carbon dioxide for photosynthesis. This allows more water to diffuse out of the leaves and into the atmosphere. Transpiration increases in daylight.
How does water supply impact on the rate of transpiration?
If the water supply is low then less water is taken up by the roots, the plant will then wilt. When the plant wilts, the stomata start to close which reduces transpiration. Low water supply reduces transpiration.
What is a potometer?
A potometer is a device used to estimate transpiration rates.
Label the potometer
What is it called when a plant grows towards a stimulus?
Tropism
What is growth towards a light called?
Phototropism
What is the hormone that controls growth towards light called, and where is it found?
Auxin, found in the tip of the stem.
What is the trophism called when a plant grows towards gravity?
Geotrophism
