If there were no atmosphere, the sky would be all black, except for the area directly around the sun, which you would not be able to look anywhere near because it would be so bright, as there would be no atmosphere to block its rays.
Contagion and contagiousness refers to how easily the spread of Genetic Disease is possible from one person to another. Other words for contagion include infection, infectiousness, transmission or transmissability. Contagiousness has nothing to do with genetics or inheriting diseases from parents.
List of Non-communicable Diseases. An NCD or non-communicable disease is a disease that is not infectious and cannot be transferred to others. Some of these are diseases that progress slowly or cause chronic symptoms while others progress very rapidly.isk Factors of NCD: Some risk factors of non-communicable diseases include the environment, lifestyle or background such as the genetics, age, exposure to air pollution or gender of a person.