Proteins

Question 0

What are the monomer units of proteins?

Answer 0

Amino acids

Question 1

Proteins are what?

Answer 1

Macromolecules

Question 2

What are proteins composed of?

Answer 2

Hydrogen carbon oxygen nitrogen and 2 amino acids also contain sulfur

Question 3

How many known amino acids are there?

Answer 3

20

Question 4

What kin of bond holds two amino acids together?

Answer 4

Peptide bond

Question 5

How long are proteins usually?

Answer 5

100-300 amino acids long

Question 6

What determines the function of proteins?

Answer 6

Their 3-D structure

Question 7

What are several functions of proteins within the human body?

Answer 7

1. Materials for building and maintaining cell membranes
2. Form hormones
3. Form enzymes
4. Last source of energy for cellular respiration
5. Form antibodies
6. Acts as a gene regulators

Question 8

Are all proteins soluble in water?

Answer 8

Yes

Question 9

What is an optical isomer?

Answer 9

When substances have the same molecular and structural formula but are mirrored.

Question 10

What are optical isomers referred to as and what are the different forms called?

Answer 10

Chiral and the different forms are called enantiomers

Question 11

What was the first protein to be sequenced?

Answer 11

Insulin which has 2 peptide chains held together by 3 disulfide prodges of cysteine and had a total of 51 amino acids

Question 12

What was the second protein to be sequenced?

Answer 12

Lysozyme which has on chain of 129 amino acids with 4 disulfide bridges. It’s found in tears and breaks down the polysaccharide walls of bacteria and prevents infection.

Question 13

Explain primary structure.

Answer 13

Order of amino acids and location of disulfide bridges.

Question 14

Explain secondary structure.

Answer 14

Hydrogen bonding can give more complex shapes. Such as an alpha helix, a beta pleated sheet or a random coil.

Question 15

Explain what an alpha helix is.

Answer 15

Complete right handed turn every 3.6 amino acids around an alpha carbon. R-groups point out. Flexible and springy.

Question 16

Explain beta pleated sheets

Answer 16

Polypeptide chains that run parallel to each other but run in opposite directions. There are hydrogen bonds that make it rigid and non stretchy.

Question 17

Explain tertiary structure.

Answer 17

If a polypeptide is folded to make a compact molecule or a globular shape. Depends if molecule is hydrophobic or hydrophilic.

Question 18

Explain myoglobin.

Answer 18

Has 153 amino acids with 8 alpha helix regions. At each segment there is a bend creating a globular structure.

Question 19

What is a congucated protein?

Answer 19

A protein that contains a non protein heme group also known as a prosthetic group.

Question 20

Explain quaternary structure

Answer 20

When there is more than one polypeptide chain that does not have covalent bonding or disulfide bridges.

Question 21

What is a protein that has all 4 levels of structure called?

Answer 21

Oligomeric proteins.

Question 22

What is each polypeptide chain in a protein called?

Answer 22

A protomer

Question 23

Proteins with the same polypeptide chains are called what? Proteins with different polypeptide chains are called what?

Answer 23

Homo-oligomers and hetero-oligomers