Amino Acids and Proteins

Question 1

What is DNA made up of?

Answer 1

Nucleotides, amino acids, sugars

Question 2

What structure does DNA form?

Answer 2

Double-helix

Question 3

Describe a Hydrogen bond

Answer 3

Forms between hydrogen and either oxygen, nitrogen or fluorine. It forms a polar bond using the high electronegativity.

Question 4

Describe an ionic interaction

Answer 4

A positively charged atom will be attracted to a negatively charged atom.

Question 5

Describe a hydrophobic interaction

Answer 5

Water is excluded

Question 6

Describe a Van der Waals interaction

Answer 6

Present between every molecule that are in close proximity.

Question 7

What property makes a molecule soluble?

Answer 7

Polarity.

Question 8

What is meant by an ‘amphipathic’ molecule?

Answer 8

Has both non-polar and polar areas in the same molecule

Question 9

In a bilayer, which way do the hydrophilic heads face?

Answer 9

Outwards

Question 10

In a bilayer, which way do the hydrophobic heads face?

Answer 10

Inwards

Question 11

List 2 properties of molecules that enable them to move through a phospholipid bilayer

Answer 11

Small
Lipid soluble
Hydrophobic
Polar

Question 12

How do molecules that cannot pass through the bilayer get into a cell?

Answer 12

Carrier proteins

Question 13

List 3 functions of proteins

Answer 13

Enzymes
Support
Transport
Receptors
/

Question 14

What are proteins made up of?

Answer 14

Amino acids

Question 15

What are the 4 groups coming off a central carbon atom in an amino acid?

Answer 15

Hydrogen
Carboxyl group
Amino group
A variable R group

Question 16

Give a definition of a Base with regard to protons

Answer 16

Proton acceptor

Question 17

Give a definition of an Acid with regard to protons

Answer 17

Proton donator

Question 18

Which stereoisomer of proteins is found in proteins?

Answer 18

L isomer

Question 19

How are amino acids classified?

Answer 19

The chemical properties of the R groups

Question 20

Will a positively charged amino acid have a high or low pK value?

Answer 20

High

Question 21

If the pH of the solution is less that the pK of the amino acid, what will happen to the amino acid?

Answer 21

The amino acid will be protonated (gain a proton)

Question 22

Describe a peptide bond

Answer 22

Two amino acids are linked by the removal of water

Question 23

List 3 properties of a peptide bond

Answer 23

Planar, shorter, rigid

Question 24

Is a cis or a trans bond found in proteins?

Answer 24

Trans- the C atoms are found on opposite sides of the peptide bond

Question 25

What is the pI of a protein?

Answer 25

The pH at which there is no net charge

Question 26

If the pI of a protein is >7, will the protein be acidic or basic?

Answer 26

Basic

Question 27

Name the part of a cell which contains DNA

Answer 27

The nucleus