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The Role of Plant Hormones
The Role of Plant Hormones
Plant hormones have a pivotal role in controlling its growth and development.
What do we call chemicals that act as messengers in plants and animals? Examples are oestrogen, testosterone, auxins, ethene etc.
Plants have hormones called auxins, gibberellins and ethene.
Auxins control growth. Gibberellins control germination of seeds (sprouting into a plant) and flower formation, as well as increase in fruit size. Ethene controls the ripening of fruits.
Plants grow at the root tips and the shoots. Which of the three hormones do you think will be present in the root tips and shoots?
When a new shoot grows from a seed, we call it germination. Name the hormone that controls germination.
Name the hormone the plant requires for growing bigger fruits.
Plants are known for bending and growing towards light. They have learned to do this because they need light to photosynthesise, otherwise they eventually die. Which hormone **** helps them grow towards the light?
Once a plant has grown its fruits, they need to ripen. Which hormone will a plant be producing when it ripens its fruits?
While plant shoots grow towards light because they need light for photosynthesis, roots grow away from light. The way plants grow in response to a condition is called a tropism. What term do you think we use for growth in response to light?
Gravity also affects plant growth because gravity acts towards the centre of the Earth. What term do you think we use for growth in response to gravity?
Plant hormones are useful to farmers and gardeners. For example, products such as weedkillers have been developed from plant hormones and unfertilised flowers are treated with gibberellins to create seedless fruits.