Root is positively geotropic but negatively phototropic whereas stem is negativity geotropic and positively phototropic. explain.

The root is geo because it grows under the ground without any contact from the sun, therefore taking in nutrients from the soil. The stem is phototropic because of it's components that are in contact with the sun and therefore creates energy from the rays.

The answers no

Gases enter the atmosphere and trap the sun's heat warning the earth.