Biological Molecules

Question 1

Alpha and beta glucose are isomers of each other- describe the difference between their structures..

Answer 1

H above OH= alpha
OH above H= beta
Draw!!!

Question 2

Monomer

Answer 2

The simplest unit, or repeating unit of a polymer

Question 3

Polymer

Answer 3

Long-chain molecules made out of sub units (monomers)

Question 4

Macromolecule

Answer 4

A large complex molecule

Question 5

Monosaccharide

Answer 5

The simplest units of carbohydrates and simplest form of sugar

Question 6

Disaccharide

Answer 6

Sugars made out of two monosaccharides, joined together with a glycosidic bond

Question 7

Polysaccharides

Answer 7

Subunits of monosaccharides that are joined together with condensation reactions

Question 8

Condensation reactions-formation of the glycosidic bond

Answer 8

A glycosidic bond is created when two or more monosaccharides join together
Condensation reaction causes the two hydroxyl groups (OH-) to align, dropping a water molecule and joining the molecules

Question 9

What is a hydrolysis reaction?

Answer 9

The opposite to a condensation reaction-causes the breakage of glycosidic bonds
Involves the addition of water to cause the components to complete the molecules with the missing H20 and therefore separate

Question 10

Characteristics and uses of polysaccharides

Answer 10

Range from highly branched to linear
Notable polysaccharides- starch (made up of amylose and amylopectin), glycogen and cellulose
Used for the storage of short chain molecules, allowing the body to have reserves of useful molecules e.g. Glucose stored as polysaccharide glycogen, making it inert until it is required

Question 11

Characteristics and uses of Triglycerides

Answer 11

Acid+ alcohol = ester
Triglycerides are chemically bonded tri esters of fatty acids and glycerol
Formed by combining three fatty acid molecules with glycerol
Provided ur body with energy but most importantly to store energy from protein, fats and carbohydrates

Question 12

Characteristics and uses of phospholipids

Answer 12

They are dipolar- heads are hydrophilic and tails hydrophobic
Used in the body to create phospholipid bilayers- fundamental feature of cell membranes

Question 13

Amino acids

Answer 13

Monomers from which all proteins are made
20 different amino acids
Each have a amine group (NH2) and and a carboxylic acid (COOH) at the other end
R group is what differentiates each 20 amino acids

Question 14

Peptide bond

Answer 14

Amino acids combine through another form of condensation reaction to create a peptide bond
NH2 looses a H molecule and COOH looses a hydroxyl (OH)
Remaining link made up of C=O and N-H ( this is the peptide bond)

Question 15

Organisation of protein catagories

Answer 15

Primary
Secondary
Tertiary
Quaternary

Question 16

Primary structure of proteins

Answer 16

The number sequence and type of amino acids that make up a polypeptide chain

Question 17

Secondary structure of a protein

Answer 17

If the structure of a polypeptide chain is an alpha helix, beta sheet, or both

Question 18

Tertiary structure of a protein

Answer 18

This is a protein with a 3D globular shape, established through the formation of various bonds between non adjacent amino acids

Question 19

Quaternary structure of a protein

Answer 19

When a protein consists of two or more polypeptide subunits

Question 20

Haemoglobin- example of globular protein

Answer 20

Consist of four polypeptide chains- two alpha and two beta
Each is associated with a heam group containing iron
Each molecule is almost a spherical shape
Aids it’s function as iron combines reversible with oxygen

Question 21

Collagen- example of a structural protein

Answer 21

Consists of long polypeptide chains, each associated with each other to form a triple helix structure
Helix is covalently bonded side to side-makes protein flexible strong against pulling forces and does not stretch

Question 22

Characteristics of water

Answer 22

Dipolar molecule- oxygen has slight negative charge and hydrogen has slight positive charge
These charges result in weak forces of attraction between adjacent molecules- called hydrogen bonding

Question 23

Why is hydrogen bonding in water significant?

Answer 23

Water acts as a solvent to substances that are hydrophilic as they can dissolve and create a solution
High specific heat capacity- large amount of energy needed to increase temperature- useful for organisms to maintain stable body temp
High latent heat of vaporisation- large amount of every needed to break bonds and change state- again helpful to maintain body temp

Question 24

Structure of glycogen

Answer 24

Similar to amylopectin but more highly branched due to 1,6 glycosidic bonds between alpha-glucose molecules forming frequently

Question 25

Structure of cellulose

Answer 25

A polymer of beta glucose
It is a structural polysaccharide found in cell walls
Long chain of cellulose molecules form bundles knows as microfibrils- become cellulose fibres
Held together with hydrogen bonding