Plant cells, tissues and organs are adapted to their functions. The stem, root and leaves form an organ system that transports substances into, around and out of a plant. The leaves are the main organ of photosynthesis.
What substances are transported in the xylem?
Water and mineral ions
Sugars and amino acids
What feature of palisade cells makes them efficient at photosynthesis?
They have a thick, waxy coating
They are packed with chloroplasts
They are very close to most of the stomata
In which direction are substances transported in the phloem?
Upwards and downwards
What is the process that transports substances in the phloem?
How is the rate of water uptake by a plant measured?
By measuring the rate of water loss from the soil
Counting the number of stomata on a leaf
Using a potometer
What type of cells release the energy required for phloem transport?
How does water enter a root hair cell?
By active transport
Why do Christmas tree growers spray the trees with a chemical that blocks the trees' stomata?
To increase the rate of photosynthesis
To reduce the transpiration rate so that they lose less water
To make them look attractive for Christmas
Which of these conditions reduces the rate of transpiration?
Increased wind intensity
Why does the rate of transpiration increase as the light intensity is increased?
The plant is respiring more so will require less carbon dioxide
The plant is photosynthessing less so will require less carbon dioxide
The plant opens its stomata to allow the entry of carbon dioxide for photosynthesis