Amino Acids

Question 1

What 2 functional groups are in Amino Acids?

Answer 1

Amino group and Carboxyl group

Question 2

What makes each amino acid different?

Answer 2

R groups: side chains

Question 3

What is a peptide bond?

Answer 3

1 amino acid’s carboxyl group bonds with another’s amino group

Question 4

What do each of these mean: Dipeptide, Oligopeptide, and polypeptide.

Answer 4

Dipeptide: 2 monomers joined
Oligopeptide: many monomers joined
Polypeptide: more than 50 monomers joined (can make proteins)

Question 5

Name the non-polar amino acids:

Answer 5

Aliphatic side chains: Glycine, Alanine, Valine, Leucine, Isoleucine

Methionine

Cysteine (can form disulphide bonds)

Aromatic: Phenylalanine, Tryptophan

Proline (link to alpha-amino group)

Question 6

What bonds can non-polar amino acids form?

Answer 6

No hydrogen bonds (hydrophobic)

Question 7

Name the polar amino acids:

Answer 7

Alcohols: Serine, Threonine, Tyrosine

Asparagine, Glutamine (amides of aspartate and glutamate)

Question 8

What minds do polar amino acids make?

Answer 8

Hydrogen bonds not ionic

Question 9

Name the charged amino acids:

Answer 9

Acidic: Aspartame, Glutamate

Basic: Lysine, Histidine, Arginine

Question 10

What bonds can be made in charged amino acids?

Answer 10

Hydrogen bonds and ionic bonds

Question 11

What are the ends of the proteins?

Answer 11

N-terminus (amino group) and C-terminus (carboxyl group)

Question 12

What bonds in a polypeptide chain are flexible and which is rigid?

Answer 12

Single bonds are flexible and double bods are rigid but the polypeptide chain itself is flexible

Question 13

Describe the secondary structure of an amino acid:

Answer 13

Interactions within polypeptide backbone

Question 14

What types of secondary structures are there?

Answer 14

Alpha helix: hydrogen bonds every 3 residues; form of a helix

Beta Pleated sheets: 2 strands folded back and forth forming hydrogen bonds across

Random coil: joins 2 structures but has no structure itself

Question 15

What are tertiary structures?

Answer 15

Interactions of side chains (R-groups)

Question 16

What types of bonds are there in the tertiary structure of the amino acids?

Answer 16

Hydrogen bonds, ionic bonds, disulphide bonds and hydrophobic interactions between R-groups

Question 17

Describe the Quaternary structure of an amino acid:

Answer 17

More than 1 polypeptide chain; interactions between 2 or more subunits of a protein

Question 18

What is a native protein?

Answer 18

Correctly folded protein and has bonds

Question 19

What do you called an unfolded protein? How are the bonds within broken?

Answer 19

Denatured proteins. Bonds are broken by putting in energy

Question 20

What is a way to analyze proteins?

Answer 20

Polyacrylamide gel

Question 21

Describe a fatty acid binding protein

Answer 21

Hydrophobic tail and a polar head with a negative charge

Question 22

How do we know the structure? Describe the steps.

Answer 22

X-ray crystallography

Single crystal gives diffraction pattern which gives the electron density map and then finally you can determine the protein model