Operons afford the organism the opportunity to
simultaneously regulate transcription of multiple genes, whose products are
active in the same process. Operons lead to the synthesis of groups of functionally
related enzymes, usually from a single mRNA transcript hence makes regulation of
the genes highly efficient.
Compound microscope is commonly used in the schools and colleges. It has two lenses, the objective lens and the ocular lens. It provides a magnification of 1500X. Eyepiece lens is of 10X or 15X power. It is used to observe bacterial, protozoa, various cells, etc.
Dissecting Microscope It is also called stereo microscope. Its magnification power is less than the other microscope. It gives a 3 dimensional picture. Due to the low magnifying power they are used to observe little bigger objects than other microscopes. They are used in the surgeries, dissection, forensic science etc.
The 'cheek' is the common name for the insect GENA.
The gena is located in the head area of insects. The gena forms the sclerotized area on each side of the head, below the compound eyes, which extends to the gular structure. The gena varies among species of insects.
The correct answer is option A,
Reason - The density of outer core is less than the density of inner core density and thus among all the given options the more probable answer is option A
