Biological Molecules

Question 1

Difference in Structure of GLYCOGEN 🦍& CELULLOSE 🌳

Answer 1

Glycogen

1. No hydrogen bonding
2. 1,4 and 1,6 glycosidic bond
3. Branched
4. No fibres
5. Granules
6. All glucose units in same orientation
7. Non helical
8. One chain per molecule
9. Contain C H O

Cellulose

1) hydrogen bonding
2) 1,4 glycosidic bond ONLY
3) Not branched / linear / straight
4) fibres
5) No granules
6) Adjacent glucose units in opposite direction
7) helical / linear
8) three chain ( per molecule)
9) Contain C H O N

Question 2

Polymer formed from a chain of amino acids

Answer 2

Polypeptide / Protein

Question 3

List 3 example where Hydrogen bond found in biological molecues

Answer 3

1. Protein secondary structure /a helix / B pleated sheet
2. Tertiary structure
3. Between polypeptide chain in amino acid quaternary structure
4. Between Cellulose chai
5. Between bases in Dna

Question 4

Importance of cholesterol

Answer 4

• Maintain / regulates fluidity of membrane
• Water proofing skin
• Steroid

Question 5

Glycogen good storage

Answer 5

:Insoluble
:Does not change or effect by water potential
:Can be broken down or hydrolysed or built up easily\quickly
:compact
:high energy content for mass
:Lots of branches for enzyme to attach

Question 6

Structure of Haemoglobin

(globular protein?

Answer 6

A sequence/chain of amino acids
Joined by peptide bond

Secondary structure is a-helix
Small region of beta pleated sheet fold
Held by hydrogen hond

Tertiary
Secondary structure /helix /polypeptide chain undergoes further coilling
3bonds interaction from disulphide , ionic, hydrogen
Hydrophobic or hydrophilic

Quaternary
4 polypeptide
2alpha 2 beta chain
1 haem group per polypeptide/ 4 haem per molecules
Prosthetic  group is haem contain fe2+

Question 7

Similarities structure of Haemoglobin and Collagen

Answer 7

Made if amino acid in a sequence

Made of peptide bonds

Helical / helix

3 bonds / interaction from disulphide / ionic / hydrogen / hydrophobic abd hydrophilic

Quaternary structure

More than one polypeptide

Question 8

Difference between lipids from animals🐆 and plants🌵

Answer 8

Solid at room temperature
Saturated
Fatty acids have no or fewer double bonds

Question 9

Properties of collagen

Answer 9

Strong / high tensile
Insoluble
Not elastic
Flexible

Question 10

Differences between globular & fibrous proteins

Haemoglobin - Globular
Collagen - Fibrous protein

Answer 10

Globular
🕸Spherical shape
🕸Hydrophilic , Rgroups regions on outside of 3D structure / hydrophobic R groups on Inside
🕸Form H bond
🕸Soluble

“Haemoglobin, carries/ transports , O2 / CO2
“Contain prosthetic group/ haem / Fe2+
“Haemoglobin have tertiary structure

Fibrous
🐚linear / long chain
🐚form h bond with adjacent
🐚insoluble
🐚provide strength
🐚have structural role
Collagen has high proportion of glycine so chains can lie close together
Collagen form cross links/ covalent bond between molecules
Collagen form parts of tendon / cartilage

Question 11

Fibrous Proteins🔻
Elastin - arterial walls tissue
Collagen - tendon & ligament tissue
Keratin- hair & nails 
Actin & myosin- muscles

Answer 11

Regular repeating sequences of amino acids.

In parallel

H-Bonds & disulphide bridges form between Side groups

Very stable & unreactive

Insoluble

Question 12

Globular

Haemoglobin
insulin
amylase

Answer 12

> Irregular sequence of amino acids
>Twisted shape held in place by Ionic , Hydrophobic , Hydrogen and Disulphide bonds.
>Polar R-groups face outward
>Unstable to heat ,pH and chemicals
>Involved in metabolic functions