What is the main function of the following organelles:
Nucleus, mitochondria,
chloroplasts, and vacuoles

Nucleus: controls activity and stores DNA

Mitochondria: generates energy for the cell

Chloroplasts: carries out photosynthesis

Vacuoles: stores water and transports

clinically, some people often have repeated allergies, eczema and respiratory infections or other parts of the infection, in this case, in addition to some routine tests such as tests for white blood cells, immunoglobulin series, lymphocyte subsets, etc., the five immune immunoglobulin tests are also necessary.

a "theory" a suggestion that is not 100 % accurate, or a figure. some people say its a theory because they of all the passed theory's about one subject. it depends sometimes theory might be accurate and sometimes they are.