The <em><u>MESOSPHERE </u></em>is the coldest layer and the hottest layer is <u><em>THERMOSPHERE </em></u> is the hottest layer in the atmosphere.

Air pollution has become an extremely serious problem. Air pollutants affect both plants and animals. Under polluted conditions, plants develop different physiological, morphological and anatomical changes. Pollutants cause damage to cuticular waxes by which then they enter the leaves through stomata. This further leads to injury to plants which can be either acute or chronic. Changes in stomata due to air pollutants which seem to be small can be of great consequence with respect to survival of the plant during stress. These effects can further lead to disturbing the water balance of leaf or whole plant. Respiration also gets affected because of the exposure of plants to air pollutants. The present paper deals with the effect of air pollutants on stomata as well as on respiration leading to affect gaseous exchange.


The number of phenotypes produced for a given trait depends on how many genes control the trait. Anyhow, The distribution of phenotypes for a typical polygenic trait can often be expressed as a bell-shaped curve.
Many traits are controlled by two or more genes and are, therefore, called polygenic traits<span>. Each gene of a polygenic trait often has two or more alleles. As a result, one polygenic trait can have many possible genotypes and phenotypes.</span>
The parents should go to gene counciling to determine who carried the gene that was passed down to the offspring.
True because some fossils only lived in certain places