Proteins (OCR A-Level Biology A): Quizzes
📚Quizzes
Practise the questions
10 questions from this quiz
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Practise the questions
10 questions from this quiz
Which elements are found in proteins? (Remember CHONS)
Which elements are found in proteins? (Remember CHONS)
Carbon, hydrogen, oxygen, nitrogen, sulfur
What does the R group determine in an amino acid?
What does the R group determine in an amino acid?
Identity, interactions, and properties
What is released when two amino acids join in a condensation reaction?
What is released when two amino acids join in a condensation reaction?
One molecule of water (H₂O)
How many different amino acids make up proteins in living organisms?
How many different amino acids make up proteins in living organisms?
20
What type of bond stabilizes the alpha helix secondary structure?
What type of bond stabilizes the alpha helix secondary structure?
Hydrogen bonds
Which bond in tertiary structure is a strong covalent bond between sulfur atoms?
Which bond in tertiary structure is a strong covalent bond between sulfur atoms?
Disulfide bond
Which type of protein is compact, spherical, and soluble in water?
Which type of protein is compact, spherical, and soluble in water?
Globular proteins
How many polypeptide chains does haemoglobin contain?
How many polypeptide chains does haemoglobin contain?
Four (two α-chains and two β-chains)
In collagen, which amino acid appears at every third position in the sequence?
In collagen, which amino acid appears at every third position in the sequence?
Glycine
What colour indicates a positive result in the biuret test for proteins?
What colour indicates a positive result in the biuret test for proteins?
Mauve/purple