1.1 Biological Molecules: Proteins Flashcards
How many amino acids are there?
20
what is a polypeptide?
A polypeptide is a large chain of two or more amino acids bonded together
What is the primary structure of a protein?
The primary structure is a long polypeptide chain of amino acids.
What groups make up a amino acid?
Carboxyl group (-COOH)
R group
Amine group (-NH2)
How do you test for a protein?
1) Place the sample into a test tube and add an equal volume of sodium hydroxide at room temperature
2) Add a few drops of dilute copper sulfate solution and mix gently
3) A purple colour indicates the presence of a peptide bond and hence a protein. A negative result would mean a blue colour meaning no colour change
What is the secondary structure of proteins?
beta pleated sheets and or coiled alpha helix both due to the hydrogen bonds
What is the tertiary structure of proteins
Disulfide bridges are formed ionic bonds and hydrogen bonds more coiling and or folding. (beta pleated sheets or alpha helixes)
What is the quaternary structure of proteins?
Made of several different polypeptide chains held together by disulfide bridges ionic bonds and hydrogen bonds forming the final 3D structure.
How are enzymes specialised?
Enzymes have a spherical shape. They have very tight folding of the polypeptide chains which forms an active site allowing substrates to fit in via an induced fit model which allows expansion around enzymes which allows for an Enzymes-substrate complex to form.
What are antibodies made of?
2 light chains of polypeptides short
2 heavy chains of polypeptides large bonded together
Why are many antibodies allowed to form?
due to the variable region.
Keratin and collagen name their properties and explain why.
physically strong as they are made of long polypeptides chains lying parallel to each other with cross-links between them
