Key Area 3
(e) Forming polypeptides
The last part of our topic on Gene Expression focuses on the final production - the protein. However, a protein isn't a protein until it is folded. The production of translation is a polypeptide. Folding of this polypeptide generates a protein with a unique function. Work through "Something to Read" and then choose at least one other activity to support your at-home learning.
Something to Read...
Open the document below and read the mandatory course notes provided by SQA for this Key Area. You may wish to use your home learning time to copy these notes into a jotter or choose a digital presentation format that suits your learning style.
Something to Watch...
I have chosen three things for you to watch to help support your understanding of this section.
The first one is a time-lapse of polypeptide synthesis and subsequent folding. This shows how the linear chain of amino acids (polypeptide) quickly assembles a 3D folded structure.
The second video is excellent and from the Protein Data Bank. It includes more detail than you require but it is worth the watch. Remember to keep in mind your key notes while you watch.
The final video is accessed by clicking the white button below. This will take you to a website with a brief summary of key functions of proteins and an accompanying video.
Something to look at...
I have included a diagram of a peptide bond below. You do not need to remember this structure - however, in the diagram you can see 2 amino acids. Through a condensation reaction, these 2 amino acids bond with the loss of a water molecule. This continues sequentially during translation at the ribosome until a series of amino acids have linked, forming a polypeptide.
I have also included this graphic to summarise the functions of proteins in the body.
You are now ready for your in-class lesson on the formation of polypetides. Remember to bring any questions or queries with you.
You are have reached the end of Key Area 3, you should return to SCHOLAR to access the features shown in the image below.
