ProteinsEdexcel A-Level Biology B: Flashcards
What these 13 flashcards ask
- What is the general structure of an amino acid?
- How is a peptide bond formed?
- How many peptide bonds are in a polypeptide of n amino acids?
- What is the primary structure of a protein?
- What holds secondary structure together?
- Name three bonds in tertiary structure.
- Which amino acid forms disulfide bonds?
- What is quaternary structure?
- How do fibrous and globular proteins differ?
- Why is haemoglobin soluble?
- How many polypeptides and haem groups are in haemoglobin?
- Describe the structure of collagen.
- Why does collagen have high tensile strength?
Exam questions on Proteins
- A biochemist synthesises a short polypeptide in the laboratory by joining amino acids together one at a time. She is checking that the bonds formed are the same as those found in proteins made in cells.Explain what is meant by the primary structure of the polypeptide and why a change in the primary structure could change the function of the protein.2 marks
- Haemoglobin is the protein in red blood cells that carries oxygen. It is soluble in the cytoplasm of the red blood cell and each molecule can carry up to four oxygen molecules.Explain why haemoglobin is soluble in the cytoplasm of a red blood cell.2 marks
- Tendons connect muscle to bone and must resist large pulling forces without stretching. The main protein in a tendon is collagen, which is a fibrous protein, whereas haemoglobin in the blood is a globular protein.Explain how the structure of collagen makes it suitable for its role in a tendon.3 marks
Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).