Growth regulators Flashcards
Define a growth regulator
A growth regulator is a chemical that controls the growth of a plant
Where and in what amounts are most growth regulators produced in a plant? What happens to these then?
Most growth regulators are produced in small amounts in one part of a plant (mainly in meristems) and transported to another part where they cause an effect.
Why are growth regulators often called hormones?
Most growth regulators are produced in small amounts in one part of a plant (mainly in meristems) and transported to another part where they cause an effect.
For this reason they are often called hormones.
What is the exact way growth regulators are transported?
. The exact way that growth regulators are transported is not known. Most, however, are transported in the vascular tissues (xylem and phloem).
Why is it difficult to establish the exact role of plant regulators? (4)
They are active in very small amounts.
Their effects depend on their concentration
Different regulators act in different ways
Their effects depend on the location in the plant in which they are acting
A growth regulator’s effect depends on its concentration. Explain this
This means the same regulator can have opposite effects at high or low concentrations.
The growth regulator’s effects depend on the location in the plant in which they are acting. GIve an example of this.
For example, the same concentration of plant regulator can have opposite effects in the stem and root.
Different regulators interact in different ways. Explain this by examples
Some regulators support each other to produce a greater effect.
Others interfere with each other and the combination may have no effect.
Growth regulators can act as growth promoters or growth inhibitors.
