L2 - molecules of life

Question 1

general formula of carbohydrates

Answer 1

nCH2O

Question 2

functional groups in carbohydrates

Answer 2

carbonyl (CHO) and hydroxyl (OH)

Question 3

properties of carbohydrates

Answer 3

hydrophilic
polar
water soluable

Question 4

what are the two classifications of monosaccharides

Answer 4

aldoses and ketoses

aldehyde group or ketone group

Question 5

how do sugars form ring structures

Answer 5

spontaneously

the ketone/aldehyde group reacts with hydroxyl group forming 5/6 membered ring

Question 6

What are D and L isomers?

Answer 6

non superimposable mirror images (optical isomers)

Question 7

how can a D sugar be determined from a L sugar

Answer 7

L isomer - OH group on the left of chiral centre

D isomer - OH group on the right of chiral centre

Question 8

what OH group determines whether glucose is D or L? (in straight formula)

Answer 8

Carbon 5 (away from functional group)

Question 9

define epimer

Answer 9

stereoisomers that differ in configuration of a single chiral C

Question 10

what are structural isomers? (examples)

Answer 10

ketose and aldoses

eg glucose and fructose

Question 11

define anomers

Answer 11

sterioisomers that differ in configuration of the anomeric carbon

Question 12

what is the anomeric carbon in glucose

Answer 12

C1

Question 13

examples of anomers

Answer 13

a and B glucose (D form)

Question 14

what is the positioning of the hydroxyl groups on a and B glucose

Answer 14

a - hydroxyl is below C1

B - hydroxyl is above C1 (then rest of OH alternate)

Question 15

what are the types of glyosidic bond?

Answer 15

a 1-4
B 1-4
aB’ 1-2
a 1-6 (in glycogen branches)

Question 16

what are the polymers of glucose in plants

Answer 16

starch (amylose and amylopectin)

Question 17

what is the polymer of glucose in animals

Answer 17

glycogen

Question 18

compare glycogen and amylopectin structure

Answer 18

similar but glucose has more branches

Question 19

functions of carbohydrates

Answer 19

1. metabolism

2. recognition molecules (glycoproteins/glycolipids)

Question 20

function of TAGs? 
where are they stored?

Answer 20

energy storage

lipid droplets in cells

Question 21

describe structure of glycerophospholipids

Answer 21

a TG but one FA is replaced with a phosphate group bound to an amino alcohol (Hphilic) via ester bonds

amphipathic (form bilayer)

Question 22

what is steroid template?

Answer 22

fused alkly rings which form the basis of all steroid hormones - they just have add ons

Question 23

describe cholesterol structure and function

Answer 23

Hphilic head and Hphobic tail
rigid

can insert into membrane to modualate fluidity

Question 24

describe nucleic acid general structure

Answer 24

pentose sugar + nitrogenous base + phosphate group

Question 25

what are pyrimidines? and give examples

Answer 25

single ring structure nitrogenous base
Cytosine
Thymine
Uracil

Question 26

what are purines? and give examples

Answer 26

double ring structure nitrogenous base
Adenine
Guanine

Question 27

what determines protein folding?

Answer 27

the charged / polar / uncharged side chains of AAs

hphilic on outside hphobic on inside

Question 28

polar& charged Hphilic (water soluble)

Answer 28

uncharged = H phobic (lipid soluble)

Question 29

properties of AAs

Answer 29

charged at pH 7 (NH+ , COO-)

water soluble

Question 30

what is special about histidine at pH 7?

Answer 30

can easily gain or lose a H+