What Are Ribosomes?

Find all the answers to your ribosome questions for worksheets and assignments in the videos and info below.

Thanks for stopping by, this is 2 Minute Classroom and today we are talking about the structure and function of ribosomes, which are a key player in protein synthesis.

Ribosomes are an underrated hero of the cell and the average mammalian cell has about 10 million ribosomes! They are made of RNA and protein and their function in the cell is to read RNA and synthesize protein, very meta.

Ribosomes have two major subunits, simply called, the large and small ribosomal subunits. Both subunits contain protein and RNA. The RNA in ribosomes is called (not surprisingly) ribosomal RNA, or rRNA for short.

In eukaryotic cells, ribosomes are synthesized in the nucleolus of the nucleus, this is an area densely packed with DNA and proteins. The location of ribosomes in the cell determines where the protein they make ends up. Ribosomes free floating in the cytoplasm of the cell synthesize proteins to be used within the cell, while ribosomes bound to the Rough Endoplasmic Reticulum synthesize proteins that will end up outside the cell, either bound to the cell membrane or released from the cell as a signaling protein for example. 

Ribosomes synthesize protein in a process called “translation” where they read strands of mRNA and bring the right amino acids together to build a long polypeptide chain that that will eventually become a functioning protein. You can learn all about transcription and translation here.

Now watch this test prep playlist if you have any exams coming up. 

Thanks for reading, and I’ll catch you next time.