The permanent gases whose percentages do not change from day to day are nitrogen<span>, </span>oxygen<span> and</span>argon<span>. </span>Nitrogen<span> accounts for 78% of the atmosphere,</span>oxygen<span> 21% and </span>argon<span> 0.9%. Gases like </span>carbon dioxide<span>, nitrous oxides, </span><span>methane</span>
Answer:
The correct answer is - A. phototropic and gravitropic.
Explanation:
A plant seedling grows usually two-direction shoots or stems towards light and roots towards the soil or in the direction of gravity. The movement of the plant toward a specific stimulus or effect parts is called tropism and different parts move in a different direction.
The movement of the roots of the plant is usually towards the direction of soil or gravity and this is called gravitropic. The shoot or stem grows from the seedling towards the direction of light and it is called phototropic.
