Biological Molecules 🍕

Question 1

Water propites

Answer 1

-Polar molecule (+/-) so adjacent molecule attracted hydrogen bonds formed between molecules making it strong
- solvent properties so dissolved compounds can transport and out if cells
- cohesive/ adhesion between molecules moves as 1 mass
-high melting point, high specific heat capacity
- temperature buffer

Question 2

Hydrophobic

Answer 2

Cannot become part of water

Question 3

Hydrolysis

Answer 3

Breaks down in present of water

Question 4

Condensation reaction

Answer 4

Produces water

Question 5

what are proteins

Answer 5

a polymer called polypeptides made up of amino acid units

Question 6

Insulin

Answer 6

• globular protein, alpha helix
• hormone that regulates blood glucose level
• 3d shape

Question 7

Hemoglobin

Answer 7

• Globular protein, alpha pleated
• conjugated protein
• bind and unbind to oxygen
• 4 polypeptide chains 2 alpha 2 beta subunits
• each sub unit contains a prosthetic haem group

Question 8

Catalase

Answer 8

• enzyme found in liver
  -conjugated proteins
• quaternary protein containing 4 haem prosthetic groups
• ensures that hydrogen peroxide (dangerous to cells) doesn’t built up in cells

Question 9

Keratin

Answer 9

-in hair skin nails
- fibrous, beta pleated sheets
- large portion of cysteine (sulphur containing amino acids)
- many disulfide bonds making it strong and inflexible and insoluble

Question 10

Elastin

Answer 10

Fiberous, beta pleated sheets
In walls of vessels, gives structures flexibility
Made from tropoelastin so can stretch and recoil
Formed when multiply tropoelastin molecules aggregate via interaction in hydrophobic areas and stabilized by cross linking covalent bonds

Question 11

Collagen

Answer 11

Fibourous, beta pleated sheets
Connective tissue found in skin tendons ligaments and ns
Made up of 3 polypeptide (triple helix)
Every 3rd amino acid is glycine so can be packed together tightly
Hydrogen bonds between polypeptide chains forming long quaternary proteins with staggered ends
R groups repel each other

Question 12

what elements in carbohydrates

Answer 12

Carbon, oxygen, hydrogen

Question 13

Glucose

Answer 13

Basic monomer of carbohydrates. Its a hexose monosaccharide which is polar and soluble in water due to hydrogen bonds and hydroxyl groups

Question 14

Condensation reaction of glucose

Answer 14

2 alpha glucose are together the hydroxyl groups interact and react. A water molecule molecule is formed, the glycosidic bond is between carbon 1 and 4

Question 15

Pentose

Answer 15

5 carbons , e.g ribose and deoxyribose

Question 16

Maltose

Answer 16

Formed of 2 glucose molecule with a alpha 1-4 glycosidic bond

Question 17

Sucrose

Answer 17

Is formed from glucose and fructose joined glucose and fructose by 1-4 glycosidic bond

Question 18

Lactose

Answer 18

Is formed from galactose and glucose by a beta 1-4 glycosidic bond

Question 19

Glycogen

Answer 19

Animials store carbohydrates as glycogen have alpha 1-6 glycosidic bonds, less dence and more soluble then starch

Question 20

Cellulose

Answer 20

Main part of plant cell wall consists of long chains of beta glucose joined by beta 1-4 glycosidic bonds. Chains form robe like microfibrils which are layered to form network

Question 21

Lipids

Answer 21

Only contain carbon, hydrogen and oxygen. Insoluble in water but soluble in organic compounds

Question 22

Triglycerides

Answer 22

A glycerol and 3 fatty acids and an ester bond. Transported around body and stored in adipose tissue

Question 23

Role of lipids

Answer 23

Lipids stored as adipose tissue. Heat insulation, buoyancy, protection

Question 24

Saturated

Answer 24

no double bonds between c

Question 25

Phospholipid

Answer 25

1 phosphoric acid and 2 fatty acids. The head is charged and hydrophilic, the tail is hydrophobic and non polar. They form spontaneous bilayre which is an essential component of cell and organelle membrane

Question 26

Testing for lipids

Answer 26

Emulsion test Mix with ethanol then water and a milky ppt forms

Question 27

Testing for proteins

Answer 27

Buiret test Peptide bonds form violet coloured complexes with copper ions in alkaline solutions. Blue to purple

Question 28

Testing for starch

Answer 28

Iodine solution. Turns from yellow to blue/black

Question 29

Testing for reducing sugars

Answer 29

Benedicts regent heat to 70c Blue - green - yellow - red Qualitative

Question 30

Testing for non reducing sugars

Answer 30

Add HCL heat to hydrolyse the glycosidic bond Add sodium hydrogen to neutralise the solution Add the benedicts reagent and heat in water bath Green - yellow - orange - red

Question 31

monounsaturated

Answer 31

one double bond between c

Question 32

Polyunsaturated

Answer 32

more than 1 double bond between c

Question 33

what do double bonds in lipid

Answer 33

Double bonds make molecules bend so they can’t pack together as tightly so liquid at room temp

Question 34

primary structure of protein

Answer 34

the order of amino acids in a polypeptide chain determined by the genetic code

Question 35

secondary structure of protein

Answer 35

amino acid chain can coil into an alpha helix or a beta pleated sheet

Question 36

tertiary structure of protein

Answer 36

whole chain further folded into a complex globular shape

Question 37

alpha helix

Answer 37

hydrogen bonds form between oxygen and hydrogen atoms

Question 38

beta pleated sheet

Answer 38

amino acid folds back upon itself forming anti parrel chains, oxygen and hydrogen that are close together form hydrogen bonds

Question 39

what does hydrogen bonds do in the secondary protein structure

Answer 39

help to stabilise structure

Question 40

quaternary structure of protein

Answer 40

multiply polypeptide chains combind and are help together by bonds

Question 41

when do disulphide bridges form

Answer 41

when R groups of 2 amino acids contain sulphur atoms and are in close proximity

Question 42

monosaccaride

Answer 42

carbohydrate, small simple sugars soluble in water

Question 43

disaccharide

Answer 43

carbohydrate large sugar soluble in water

Question 44

polysaccharide

Answer 44

long chain carbohydrate insoluble in water

Question 45

monosaccharide example

Answer 45

glucose, fructose, ribose

Question 46

disaccharide example

Answer 46

lactose, sucrose

Question 47

polysaccharide example

Answer 47

glycogen, cellulose, starch