The Effect of Internal and External Factors on Growth of Plant
Effect of Light
They’re comparing the growth of plant in two different condition , one grown in darkness and the other exposure to light
Why plant in darkness elongate more than the plant exposure to light?
they explain it’s caused by the plant growth hormone called auxin Auxin promotes cell growth stimulates plant cells to elongate.
When a plant bends toward the light, the auxin concentration is higher on the side away from the light, these cells elongate more and this causes the seedling to bend so that it’s facing the light, but the chlorophyll produce well in the plant that exposure to light.