Question
Biology Question on Cell: the unit of life
An outer covering membrane is absent over
A
nucleolus
B
lysosome
C
mitochondrion
D
plastid.
Answer
nucleolus
Explanation
Solution
An outer covering membrane is absent over nucleolus. Nucleolus is a dense, spherical, colloidal body which remains attached with nucleolar organizing chromosomes. It was discovered by Fontana (1781) and termed as nucleolus by Bowman (1840). The main function of nucleolus is the synthesis of ribosomal RNA and it is called store house of RNA. It plays important role in cell division also.