Lipids 1

Question 1

Classification

Answer 1

Simple»
Triglycerides» oils/fats
Waxes
Conjugated simple+other group
Derived hydrolysis or associated

Question 2

Definition of lipids
Formula

Answer 2

Organic compounds that are related to fatty acid esters
Alcohol+fatty acid»(esterification) triglyceride

Question 3

Dietary importance

Answer 3

High energy 9kcal
Fat soluble compounds
Essential fatty acids
In plasma, adipose,membranes

Question 4

Why are triglycerides neutral?

Answer 4

Due to loss of OH (-ve charge) during esterification

Question 5

How lipids move in blood

Answer 5

Lipoproteins

Question 6

Where are free fatty acids

Answer 6

In plasma

Question 7

Natural fatty acids are..

Answer 7

Monocarboxylic(even no.of C)

Question 8

Formula

Answer 8

Ch3-(ch2)n-cooh
N = total C-2

Question 9

Numbering fatty acids

Answer 9

C numbering»from COOH
Greek»first C after COOH (alpha-beta)
Omega»from terminal methyl group

Question 10

Classification acc to length+ examples

Answer 10

Short [6>]&raquo_space; butyric
Medium[6-10]&raquo_space;caproic
Long [12-18]»palmatic/stearic
Very long[>20]»arachidonic/lighoceric

Question 11

Palmatic and stearic are…

Answer 11

Saturated
16 C
18C

Question 12

Archidonic and lignoceric are..

Answer 12

20C
24C

Question 13

Why are unsaturated fatty acids liquid

Answer 13

Due to the presence of cis bonds which form kinks

Question 14

Classification acc to double bond

Answer 14

Saturated>most common, increased intake, increased cholesterol levels
Unsaturated>trans, cis

Question 15

Trans
What
Hazards

Answer 15

Formed during hydrogenation of vegetable oils
1.compete with essential fatty acids, causing deficiency
2.hyoercholesterolemia + atherosclerosis

Question 16

Cis

Answer 16

Monoenoic> 1 double bond
Palmitic w7:16:1
Oleic w9:18:1
Nervonic 19:24:1
Polyenoic (PUFA)> more than 1 double bond
W3» a linolenic 18 c/timnodonic 20c
W6» linolei 18c /archidonic 20 c

Question 17

Importance of PUFA

Answer 17

Eicosanoids, lipoxins and prostaglandins
Phospholipid formation

Question 18

Classification acc to nutritional value

Answer 18

Essential (not synthesised in body)» a linoleic/linoleic
non essential&raquo_space;formed from carbs

Question 19

Is archidonic essential?

Answer 19

No cuz its synthesised except in the absence of linoleic(which it is synthesised from) it becomes essential .

Question 20

Fatty acids deficiency

Answer 20

Dermatitis in infants
Fatty liver
Growth retardation
Defective sperms
Brain and retina defects

Question 21

Fatty acids reactions with carboxylic group

Answer 21

Esterification (glycerol+ 3 fatty acids> TAG+ H2O)
Salt/soap(fatty acid+ NaOH> RCOONa + H2O)
Double Reduction(RCOOH>RCHO>RCH2OH)Fatty alcohol

Question 22

Reactions with double bonds

Answer 22

Oxygen»USFA > peroxide
Hydrogen» (oleic +2 h> stearic)(linoleic+ 4h >stearic)

Question 23

Dangers of peeoxides

Answer 23

Destructs lipoproteins and cell membranes by splitting fatty acid chains.

Question 24

Eicosanoids

Answer 24

Hormone like molecules
From PUFA with 20C
No. Under name= no. Of double bonds

Question 25

Classification of eicosanoids

Answer 25

Cyclic(prostanoids)>> prostaglandins/prostacyclins/thromboxanes Acyclic>>leukotriens/ lipoxins

Question 26

Why are eicosanoids not hormones

Answer 26

Act locally Produced in small amounts all over the body Not stored Short half lives

Question 27

Prostaglandins importance

Answer 27

Promote inflammation Reproduction process(ovulation+ uterine contraction) Inhibits gastric secretion PGE2>vasodilation PGF2a>vasoconstriction

Question 28

Prostacylins Vascular epithelium

Answer 28

Vasodilation Inhibit platelet aggregation

Question 29

Thrombaxanes by platelets

Answer 29

Vasoconstriction Promote platelets aggregation (thrombus)

Question 30

Leukotriens by leukocytes during anaphylaxis

Answer 30

Respiratory distress Broncho constriction Low blood pressure Shock Inhibited by drugs like singulare