Question

answer in one word What is blank looking structure in an onion cell?​

Answer 1

Answer:

vacuoles

Under the microscope, blank-looking structures in the cytoplasm are called vacuole. It could be single and big as in an onion cell. Cheek cells have smaller vacuoles.

Answer 2

$\huge\underline\mathrm\red{ANSWER}$

The blank looking structures  are called vacuoles which are present in the cytoplasm of an onion cell which can be seen under the microscope.