Answer:
The phrase "disease is an agent of natural selection" means that those individuals which carry specific genes to resist the disease will be selected by the nature, whereas those individuals which that don't have or not capable of developing resistance genes will be excluded.
It is a well-established fact that diseases (mainly outbreaks) are best action of nature to select only those individuals which can modify there genetic material and thrive against the changing environmental conditions. Let's take the example of Coronavirus outbreak (COVID-19) this year. From the statistics we know that old people that develop the disease are most likely killed within a few days. However, young people can develop immunity against the virus easily. Hence, nature selects young people and exclude older people. This natural phenomenon is however driven by the disease.
<span>They are composed into vesicles. They may also form lysosomes. Vesicles are packages with the main intent of transporting things out of and around the cell. Lysosomes help the cell digest its food. All vesicles are destined to be sent to a specific place inside the cell.</span>
Because trees provide air?
Fats and lipids are hydrophobic which makes them water repelling compounds. Therefore, presence of a waxy coating on the outer skin of the desert plant prevents loss of water via evaporation from the skin of the plants. This helps the plant store water and increases its survival period. Hope this helps ..............)