A2.2 Cell structure (Cells): Practice Questions

What is the primary function of the nucleolus within the eukaryotic nucleus?

Where are proteins destined for use within the cytosol typically synthesized in a eukaryotic cell?

In a pulse-chase experiment using radioactive sulfur (\( ^{35}\text{S} \)) to label proteins, in which sequence will the radioactivity move through the organelles of a cell specialized for secretion?

What is the primary function of the Golgi apparatus within a eukaryotic cell?

What is a major advantage of compartmentalization provided by membrane-bound organelles in eukaryotic cells?

Which membrane-bound organelle is typically much larger in a mature plant cell compared to an animal cell, and what is its primary function in maintaining the cell's structural integrity?

Explain how compartmentalization in eukaryotic cells allows for incompatible metabolic processes to occur simultaneously within the same cell.

Based on the provided diagram of an electron micrograph, calculate the actual width of the organelle in micrometers (\( \mu m \)).

Identify the specific organelles described in the following cellular functions:

(a) The site of assembly for ribosomal subunits within the nucleus.
(b) A membrane-bound sac containing hydrolytic enzymes used for the digestion of macromolecules and damaged organelles.
(c) A network of membrane-bound sacs and tubules that lacks ribosomes and is involved in the synthesis of lipids and the detoxification of drugs.

Many eukaryotic cells exhibit extensive compartmentalization through their membrane-bound organelles. Describe the distinct roles of the rough endoplasmic reticulum (RER) and the Golgi apparatus in the synthesis, modification, and transport of proteins destined for secretion from the cell or insertion into the plasma membrane. Explain how these two organelles cooperate in this pathway.