The single-unit membrane structure present in the cytoplasm in the form of a network is:

$RER$ is well-developed in cells that are actively involved in the synthesis of:

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.
Assertion $(A)$: The primary function of the Golgi apparatus is to package the materials made by the endoplasmic reticulum and deliver it to intracellular targets and outside the cell.
Reason $(R)$: Vesicles containing materials made by the endoplasmic reticulum fuse with the cis face of the Golgi apparatus,and they are modified and released from the trans face of the Golgi apparatus.
In the light of the above statements,choose the correct answer from the options given below:

What was the contribution of the scientist Camilo Golgi in $1898$?

The network of tubular structures scattered throughout the cytoplasm is known as:

Which cell structure is shown in the given figure?