Ololol

The NUCLEUS (“mayor of city hall”)

The nucleus houses the majority of genetic material of a cell. The nucleus is the “brain” of the cell and controls all activity within the cell. Using DNA as a blueprint

(like the blueprints of a city) the nucleus directs the production of proteins.  You will learn about this process in the DNA Transcription and Translation lab.

A nucleus with the DNA coiled into chromatin.                Electron microscope picture of a nucleus

RIBOSOMES (“lumber or brick yard”)

The ribosomes carry out manual labor in the form of protein synthesis for the nucleus. They bring together all the raw ingredients such as RNA (copies of the original DNA blueprints) and amino acids to assemble proteins. The proteins created are essential to cell and organismal function.  Think of proteins as machinery for cell functions much like electricity and plumbing are essential in a real city.  For example, enzymes are a type of protein without which life could not exist.

The large and small subunits of ribosomal RNA translating an mRNA strand into a polypeptide chain.

Refer to DNA Transcription and Translation for further reading.

The ENDOPLASMIC RETICULUM (“highways and road systems”)

There are two types of endoplasmic reticulum (ER) – Smooth ER and Rough ER. This extensive network makes up approximately one half of all membranous tissue of the cell and is the site of membrane and protein synthesis. The ER system is much like a road system along which industry can be found. Goods are manufactured and shipped to needed areas via the road system. Rough ER is named for the presence of ribosomes along its membrane and is the source of proteins. Smooth ER lacks ribosomes and is responsible for lipid synthesis and processes a variety of metabolic processes such as drug detoxification.

Can you tell the difference between the smooth and rough ER?

CELL MEMBRANE (“City Border”) and CELL WALL (“City Wall”)

Cell...