Answer:
Pandemics occur for two reasons. The first is a change in the infectious agent and the second is in human patterns. Both involve exposing people to agents they don’t have resistance to. Diseases like SARS, avian flu, and the famous Spanish flu all involved a mutation in the virus that resulted in a new disease that no one had resistance too. Examples of the second are when new groups of humans make contact, like small pox amongst native Americans, and possibly the black death.
Explanation:
The
Thymocyte progenitors enter the subcapsular region of the thymus as
double-negative cd3- t cells where the double negative refers to lack of
cluster determinants CD4 and CD8. Double-negative cd3- t cells exist as small population
that is 1%-5% of lymphocytes in the lymphoid organs and peripheral blood of
humans and normal rodents.
The disorder physiologically processes associated with a disease or injury
Answer:
The wave nature of light is the fundamental resolution of an optimal instrument.
Explanation:
All the optical instruments are working on light that's why they are known as optical instrument. Optics means the behavior of light or sight. Light is an electromagnetic radiation which comes in the category of electromagnetic spectrum. It travels in the form of wavelength.
So, optical instruments are based on wave nature of light.