Bio Mols Proteins

Question 1

What 4 elements do proteins contain

Answer 1

Carbon 
Hydrogen 
Oxygen 
Nitrogen 
Sometimes sulphur

Question 2

What is the monomer sun Inuit of proteins

Answer 2

Amino acids

Question 3

How many proteins are commonly occurring in all living organisms

Answer 3

20

Question 4

What two groups do amino acids always have?

What group differs in amino acids?

Answer 4

Amino agouti NH2
Carboxylic acid group COOH

Differ in the atomic group R

Question 5

Amino acids are joined by what reaction?
What bond?
What’s the formulae of the bond

Answer 5

Condensation

Peptide bond COHN

Question 6

Two amino acids join to form a

Answer 6

Dipeptide

Question 7

Many amino acids join together in a chain to form

Answer 7

Polypeptide

Question 8

What does a protein consist of

Answer 8

One or more polypeptides

Question 9

What is the general structure of an amino acids

Answer 9

H. R. Double bond O

      N.        C.            C 

H H OH

Question 10

What is the amino acids formulae

Answer 10

NH2

Question 11

What is the carboxylic acid formula

Answer 11

COOH

Question 12

How can proteins be hydrolysed

Answer 12

Heating with acid

Using the enzyme proteases at the optimum temp

Question 13

How do proteins vary 3

Answer 13

Number and type and sequence of amino acid

Question 14

How are proteins classified

Answer 14

Occurring to their structure

Question 15

What is the primary structure of a protein 3

Answer 15

Sequence of amino acids
Joined by peptide bond
On polypeptide chain

Question 16

What does the sequence of amino acids determine

Answer 16

The specific shape of the protein

Question 17

What does the secondary structure refer to? 
Why? 
What bonds form? 
Between where?
5 
What structures?

Answer 17

The folding or
Coiling
Of the polypeptide chain as a result of hydrogen bonding between the amino acids

Alpha helix or beta pleated sheet

Question 18

What is the tertiary structure

What does this determine in enzymes

Answer 18

Further coiling and folding of secondary structure due to
Hydrogen Ionic and Disulfude bridges

Determines the shape of the active site and its precise function in enzymes

Question 19

What two types of tertiary proteins are thee

Answer 19

Globular

Fibrous

Question 20

What is a globular protein?
Example 2
Are they soluble
Do they have a specific structure

( from alpha helix)

Answer 20

Highly folded and coiled polypeptide chain to produce compact and complex tertiary structure.
Eg enzymes and antibodies
Soluble and have specific structure

Question 21

What is a fibrous protein structure
Are they soluble
What is their function
Eg

(From beta pleated sheet)

Answer 21

Long and thin and insoluble
Structural functions
Eg keratin in hair
Collagen in tissue

Question 22

What do quaternary structure relate to?

Which bonds?

Eg

Answer 22

Complex protein consisting of more than one polypeptide chain

Ionic bonds, hydrogen bonds, disulfide bridges and hydrophobic interactions

Proteins will behave similarly to phospholipids in water; the polar groups will form favorable interactions on the surface with water, while the hydrophobic groups will be in the core and away from the water molecules. Usually, amino acids with non-polar residues will be found in the core of proteins.

Question 23

What is denaturation of proteins

Answer 23

Altercation in the tertiary structure of a protein

Often irreversible of the 3D shape and is no longer functional

Question 24

What is denaturation usually caused by?
What can cause this? 3
Which bonds are not broken at the temperature?

Answer 24

Breaking hydrogen and ionic bonds
Disulfide bonds

High temperature
Extreme change in pH
Heavy metals

Question 25

What is the test for protein

Answer 25

Biuret test

Question 26

Explain the biuret test

Answer 26

Add Biuret reagent = purple present Remains blue not present