The cell theory teaches that

The correct answer for the blank is -

Cell is the basic structural and functional unit of all life forms, all living organisms are composed of basic unit called cells, and each cell arise from a previously existing cell.

Explanation -

The Cell theory was proposed by Schleiden and Schwann in the year 1839, according to which -

1) Cell is considered as the basic structural and functional unit of all life forms.

2) All life forms are made up of cell.

3) Every cell arise from a cell that already existed before.

answer; i believe that the correct answer is ; males are hemizygous for the x chromosome;