Recap amino acids and proteins

Question 1

What are the two types of Stereoisomerism ?

Answer 1

Geometric Isomerism - rotation prevents double bonding

Optical Isomerism - non- super?. Mirrior image

Question 2

Explain R groups?

Answer 2

The rest of the chain could be anything -i.e.- R groups vary in amino acids

Question 3

Explain Long straight chain aliphatic?

Answer 3

2-3 carbon side makes it hydrophobic

    |   |   |   |
  -c-c-c-c-           Makes molecules
    |   |   |   |.            Makes them twist

Question 4

What is Amine and Primary amine?

Answer 4

Alcohol/hydroxyl - Primary amine has Nitrogen

Amine- Oxygen - important has oxygen

Question 5

Explain the functional group Alkaline?

Answer 5

• Double bonded, Normal energy’s won’t change configurations
• Double bond allows us to see RETANIN.

Question 6

What dose the Phenyl group allow for?

Answer 6

Allows for swirl of molecules

Question 7

Explain the functional group Carboxylic acid?

Answer 7

• Joined with amine makes amino acids - properties of the two keeps PH in body at correct balance (buffers)
• Can give up hydrogen amine can accept

Question 8

Explain Geometric Isomerism CIS AND TRANS?

Answer 8

When the body wants to respond to a stimuli

Assist groups match TRANS at opposite sides CIS at different sides

Can assist and transfer, single bonds can rotate easily DBL can.

Question 9

Explain Optical isomers?

Answer 9

• Can change at different temperatures, changes properties of molecules.
• CHIRAL - mirror images
• Simple has 4 diff groups attached to a central carbon atom
• Carbon atom knows as the CHIRAL CENTRE can create an isomer

Question 10

All amino acids are (L) why?

Answer 10

They are all L as sugar tends to be D dees eat L more energy efficient as they won’t have to produce their own L’s

Question 11

What are proteins for?

Answer 11

1) Calalysis for DNA Polymerase
2) Transport - hemoglobin trasports 02 in the body
3) Structure - of collegen( connective-tissue) Keratine in hair nails
4) Motion of muscles i.e. Use of myosin and actin

Question 12

What are amino acids the right molecule for the functions that proteins need to preform?

Answer 12

• They can form polymers (long chains) can make different shapes from polymers
• They can act as buffers and regulate PH within the body

Question 13

What is the structure of Aa’s ?

Answer 13

R
| COOH
NH2- CH

Question 14

What is the R group in Glycine why is it significant?

Answer 14

Glycine has a hydrogen atom in the position of an R-group, dose not have a side chain (hydrophilic and non polar)

No chiral centre

Question 15

Which are the simplest amino acids, which are there side groups?

Answer 15

H.
NH2 - CH - COOH

          GLYCINE 

            CH3
              |    NH2 -   CH - COOH

   ALANINE 

BOTH non polar + charged R groups are Methyl and Hydrogen

Question 16

Name the amino acid which is unique in that the alpha amino group is attached directly to the side chain; forming a ring and making the alpha carbon a direct substituent to the side chain??

Answer 16

Proline it helps to form a secondary structure, two folding next to each other could form a beta pleated sheet

Question 17

Why is protein important?

Answer 17

Important as it is capable of folding back on its self?

Question 18

What would be the characteristics of an animal acid that is, Aliphatic?

Answer 18

R-groups are non polar, hydrophobicity increase its increasing number of C atoms .

Question 19

What would be the characteristics of an amino acid that is polar but uncharged ?

Answer 19

Usually hydrophilic, polar functional groups in the side chain

Can form hydrogen bonding with water so capable of interacting with water

Question 20

What would be the characteristics of an amino acid that is, positively charged?

Answer 20

Will contain amine groups

Question 21

What would be the characteristics of an amino acid that is negatively charged ?

Answer 21

Will contain carboxylic acid groups

Question 22

Draw glycine that has a Acidic PH?

Answer 22

H

H2N-CH-COOH

Question 23

Draw glycine with a AlkelinePH ?

Answer 23

HN3-CH-COOH.

In acid alkaline will take an acid becoming +

Question 24

Explain Glycine with a Neutral PH?

Answer 24

Changes depending on environment it is in

Zwitterion can be + and - charged at the same time

Question 25

Why is the property of amino acids to be ionised differently at different PHs important ?

Answer 25

Important as it can be a buffer

Question 26

What type of bonding occurs in primary structure, the secondary and the tertiary structure ?

Answer 26

Zwitterion bonding

Question 27

What type of bonding occurs in the primary structure of amino acids?

Answer 27

Primary structure is healed together by covalent bonds such as a peptide bonds, they are strong bonds

Or the bonding between the amino acid and the carboxylic acid groups gives a condensation reaction

Question 28

What type of bonding occurs in the secondary structure of proteins?

Answer 28

Alpha or B beta pleated sheets, are held together by hydrogen bonds

These bonds are easily denatured

Question 29

What type of bonding occurs in the Tertiary structure of proteins?

Answer 29

Vanderval bonding forces bonding between R-groups

Ionic bond + and - attract

Question 30

The spiral turn in a alpha helix contains 3.6 residues, why can it be 3 or 4?

Answer 30

Needs 3.6 as it gives the right bonding oxygen can easily bond to hydrogen to form a hydrogen bond .

Question 31

What amino acids, if they appeared next to each other would start to disrupt an alpha helix and instead might be more likely to make the protein form into a beta pleated sheet??

Answer 31

Proline big odd group forces folding