All organisms in the be viewed using a microscope

Kingdom protista

Explanation:

For most individuals, the first images seen through the lens of a microscope are protists -- unicellular organisms that don't possess enough characteristics to be defined as purely plant or animal.

regulation of gene expression. gene expression can be regulated by various cellular processes with the aim to control the amount and nature of the expressed genes. these regulatory proteins bind to dna and send signals that indirectly control the rate of gene expression

explanation:

answer; polycythemia is the correct answer;