Proteins (intro)

Question 1

What are two common examples of proteins?

Answer 1

Enzymes and (peptide) hormones

Question 2

What are enzymes?

Answer 2

Catalysts in biochemical reactions

Question 3

What are hormones?

Answer 3

Long-distance chemical signals released by endocrine cells

Question 4

What are the monomers that make up proteins?

Answer 4

Amino acids

Question 5

What is a polypeptide?

Answer 5

A linear chain of amino acids

They make up proteins.

Question 6

What is an amino group?

Answer 6

NH2

Question 7

What is a carboxyl group?

Answer 7

COOH

Question 8

Describe the central structure of an amino acid.

Answer 8

An alpha carbon bonded to an amino group and a carboxyl group

Question 9

What is the physiological pH?

Answer 9

7.2-7.4

Question 10

What is the typical charge on an amino acid’s amino group at physiological pH (7.2-7.4)?

Answer 10

Positive (protonated)

Question 11

What is the typical charge on an amino acid’s carboxyl group at physiological pH (7.2-7.4)?

Answer 11

Negative (deprotonated)

Question 12

What determines the identity of an amino acid?

Answer 12

The ‘R’ group

Question 13

What is the bond between amino acids in a polypeptide chain called?

Answer 13

Peptide bonds

Covalent and intramolecular.

Question 14

Describe peptide bonds.

Answer 14

Intramolecular bonds (covalent) between the amino and carboxyl groups of different amino acids

Question 15

How are peptide bonds formed?

Answer 15

In dehydration synthesis reactions

Also known as condensation.

Question 16

What part of the amino acid included in a polypeptide chain forms a bond with a new amino acid?

Answer 16

The carboxyl group

Binds to the amino group of the incoming amino acid.

Question 17

What is the amino (N-) terminus in a polypeptide chain?

Answer 17

The side of a polypeptide where there is an un-bonded amino group

Question 18

What is the carboxyl (C-) terminus in a polypeptide chain?

Answer 18

The side of a polypeptide where there is an un-bonded carboxyl group

Question 19

What are the different ‘levels’ of protein structure?

Answer 19

Primary, secondary, tertiary, and quaternary

Question 20

Describe a primary level protein structure.

Answer 20

A linear polypeptide chain

Question 21

What bonds are present in a primary level protein structure?

Answer 21

Only peptide bonds

Question 22

Describe a secondary level protein structure.

Answer 22

A ‘folded’ or ‘spiraled’ polypeptide chain

Question 23

What bonds are present in a secondary protein structure?

Answer 23

Peptide bonds (covalent) and hydrogen bonds (intramolecular)

Question 24

What is a beta pleated protein sheath?

Answer 24

Different secondary (folded) polypeptide chains are bonded to each other with hydrogen bonds

Question 25

What is a tertiary protein structure?

Answer 25

Bonding within the polypeptide chain between the R-Groups of different amino acids

Question 26

What types of bonds are present in tertiary protein and why?

Answer 26

Tertiary folding is the result of the outside environment, allowing for many possibilities of bonding between R-Groups

Question 27

What is the quaternary protein structure?

Answer 27

Protein consisting of more than one amino acid chain