PL5 - Proteins in 3D Flashcards Preview

A2 Chemistry (PL) > PL5 - Proteins in 3D > Flashcards

Flashcards in PL5 - Proteins in 3D Deck (17)
Loading flashcards...
1
Q

What are the three levels of protein structure?

A

Primary, secondary, and tertiary

2
Q

What is the primary structure of a protein?

A

The order of amino acid residues

3
Q

What is the secondary structure of a protein?

A

The coiling of parts of the chain into a helix or folding into a pleated sheet

4
Q

What is the tertiary structure of a protein?

A

The folding of the secondary structure to create a specific 3D shape

5
Q

How is the secondary structure of a protein held toegether?

A

Hydrogen bonds between the -NH groups on one peptide link and the C=O on another

6
Q

What types of bond hold the tertiary structure together?

A

Intermolecular bonds, ionic bonds, and covalent bonds

7
Q

Where do instantaneous-induced dipole bonds tend to form in the tertiary structure?

A

Between non-poar amino acids.

These tend to be found in the centre of proteins

8
Q

Why do non-polar amino acids tend to be found near the centre of proteins?

A

So that the id-id bonds they make don’t interfere with the H-bonding with the surrounding water molecules

9
Q

Where in the tertiary structure do hydrogen bonds tend to form?

A

Between polar side chains

10
Q

What can happen to a protein is amino acids with polar side chains are situated on the outside of its 3D structure?

A

It can form H-bonds with the surrounding water molecules and thus dissolve

11
Q

Where in the tertiary structure do ionic bonds form?

A

Between ionisable side chains

12
Q

Give an example of a covalent bond that might form in a protein’s tertiary structure

A

Between oxidised -SH groups on neighbouring cysteine residues to form -S-S- links

13
Q

What does the shape of the tertiary structure vary according to?

A

The function of the protein and what amino acids make it up/where they’re situated

14
Q

What type of secondary structure are structural proteins mostly comprised of?

A

Helices

15
Q

What type of secondary structure do globular proteins contain?

A

Both helices and pleated sheets

16
Q

Give examples of some structural proteins

A

Those in muscles and hair

17
Q

Give some examples of globular proteins

A

Hormones and enzymes