Structure of proteins - 3.6 - (2)

Question 1

Primary structure - What occurs in the primary structure?

Answer 1

this is where the amino acids are joined together

Question 2

Primary structure - What is this sequence directed by?

Answer 2

the information that is carried within DNA

Question 3

Primary structure - What will the specific amino acids in the sequence have an effect on?

Answer 3

how the polypeptide folds to give the protein’s final shape - this determines its function

Question 4

Primary structure - What are the only bonds that are involved in the primary structure of a protein?

Answer 4

peptide bonds

Question 5

Secondary structure - Which atoms of the repeating structure of the amino acids interact?

Answer 5

oxygen, hydrogen, and nitrogen

Question 6

Secondary structure - What may hydrogen bonds form within?

Answer 6

the amino acid chain

Question 7

Secondary structure - When the hydrogen bonds form within the amino acid chain, what does this do?

Answer 7

it pulls it into a coil shape called an alpha helix

Question 8

Secondary structure - What can polypeptide chains also be parallel to?

Answer 8

one another joined by hydrogen bonds - this forms sheet-like structures

Question 9

Secondary structure - What does the pattern formed by the individual amino acids cause?

Answer 9

the structure to appear pleated, hence the name beta pleated sheets

Question 10

Secondary structure - What are secondary structures the result of?

Answer 10

hydrogen bonds

Question 11

Secondary structure - What does it form at?

Answer 11

regions along long protein molecules - this depends on the amino sequences

Question 12

Tertiary structure - What is this?

Answer 12

the folding of a protein into its final shape

Question 13

Tertiary structure - What does this include sections of?

Answer 13

secondary structure

Question 14

Tertiary structure - What does the coiling or folding of sections of proteins into their secondary structures bring?

Answer 14

it brings R-groups of different amino acids closer together so they are close enough to interact

Question 15

Tertiary structure - What will occur?

Answer 15

further folding of these sections

Question 16

Tertiary structure - List the interactions that occur between the R-groups

Answer 16

hydrophobic and hydrophilic interactions - weak interacts between polar and non-polar R groups

hydrogen bonds - these are the weakest of the bonds formed

ionic bonds - these are stronger than hydrogen bonds and form between oppositely charged R-groups

disulfide bonds - these are covalent and the strongest of the bonds but only form between R-groups that contain sulfur atoms

Question 17

Tertiary structure - What does this produce?

Answer 17

a variety of complex-shaped proteins, with specialised characteristics and functions

Question 18

Quaternary structure - What does this result from?

Answer 18

the association of two or more individual proteins called subunits

Question 19

Quaternary structure - What are the interactions between the subunits the same as?

Answer 19

in the tertiary structure except that they are between different protein molecules rather than within one molecule

Question 20

Quaternary structure - What can be identical or different?

Answer 20

the protein subunits

Question 21

Quaternary structure - What do enzymes consist of?

Answer 21

two identical subunits whereas insulin (a hormone) has two different subunits

Question 22

Quaternary structure - What is haemoglobin?

Answer 22

a protein required for oxygen transport in the blood, has four subunits, made up of two sets of two identical subunits