Which of the following are covered by a single membrane?

Name two double membraned cell organelles.

Silver nitrate solution is used to study which of the following cell organelles?

When do chromatin fibres organize themselves into chromosomes?

Cell secretions are done by

Name the organelles which show the analogy written as under:
$(a)$ Transporting channels of the cell ..........
$(b)$ Power house of the cell ............
$(c)$ Packaging and dispatching unit of the cell ...........
$(d)$ Digestive bag of the cell ...........
$(e)$ Storage sacs of the cell ...........
$(f)$ Kitchen of the cell .............
$(g)$ Control room of the cell ..........