Proteins

Question 1

What are some properties of proteins

Answer 1

• 3D folded and coiled molecules- structure fits function
• 50% of dry mass in most cells
• composed of 1 or more polypeptides

Question 2

What are the functions of proteins?

Answer 2

• assist in chemical reactions

- provide support in movement

Question 3

Define hydrolysis

Answer 3

Breaking down using water

Question 4

What is the reaction that occurs when monomers are reacting?

Answer 4

Monomer + monomer - polymer + H2O

Question 5

What are some properties of assembling polymers?

Answer 5

• Sometimes energy can be required
• assisted by enzyme
• water molecule produced for every monomer added

Question 6

What are some properties of breaking apart polymers

Answer 6

• addition of water molecule
• assisted by enzyme
• releases energy
• uses one water molecule for each break

Question 7

How many monomers are in a protein polymer and what are the monomers called?

Answer 7

~50-34000 monomers

Amino acids

Question 8

What is the structure of a amino acid?

Answer 8

Central carbon
Carboxyl and amino
Side chain variable groups

Question 9

How many major amino acids are there?

Answer 9

20

Question 10

What are the properties of amino acids based on properties of R groups at PH7.2

Answer 10

Uncharged: polar, non polar
Charged: acid, base

Question 11

What holds amino acids together?

Answer 11

Peptide bonds formed by a dehydration reaction

Question 12

What is the primary structure of a protein?

Answer 12

Unique sequence of amino acids held together by peptide bonds (covalent bonds)

Question 13

If a secondary structure protein is rich in beta it is what? Rich in alpha?

Answer 13

Beta- arrest has and recoil (spider web)

Alpha- fibrous and strong (horns)

Question 14

What are some properties of a secondary protein structure

Answer 14

Shape: helixes or sheets

-held together by H bonding by points in backbone (spiral or squiggle shape)

Question 15

What are some properties of a tertiary structure?

Answer 15

• 2 or more secondary structures held together
• interactions between side chains
• hydrophobic interactions in non polar side chains
• hydrogen bonding between polar side chains
• ionic bonds (disulphides)

Question 16

What are the quaternary protein structures and describe them

Answer 16

Globular- 2 alpha and 2 beta chains

Fibourus- polypeptides coiled

Question 17

What is a denatured protein

Answer 17

When it has lost proper 3D structure