Lesson 3 : Lipids

Question 1

● Lipids with Fatty Acids
● Lipids without Fatty Acids

Answer 1

● Lipids with Fatty Acids
○ Waxes
○ Fats and oils (Triglycerides)
○ Phospholipids
○ Sphingolipids
● Lipids without Fatty Acids
○ Steroids

Question 2

What is TRIACYLGLYCEROL

Answer 2

● Energy storage lipids.
● Found in Adipocytes (Adipose cells).
● Formed by esterification of glycerol and 3 fatty acids.

Question 3

process of combining an organic with an alcohol to form an ester with water.

Answer 3

Esterification

Question 4

The esterification of the triacylglycerol is a

Answer 4

dehydration synthesis reaction where fatty acids and glycerol are combined to form an ester bond and release water.

Question 5

differentiate simple Triacylglycerol from a mixed Triacylglycerol

Answer 5

● Simple Triacylglycerol - triester formed from esterification of glycerol with 3 identical fatty acids.

● Mixed Triacylglycerol - triester formed from the esterification of glycerol with more than 1 kind of fatty acid.

Question 6

naturally occurring mixtures of triacylglycerol in which many different triacylglycerol molecules are present which are ______ or _______ at _______ temperature (__C).

Answer 6

Fats
solid / semi-solid
room
25C

Question 7

naturally occurring mixtures of triacylglycerol in which many different triacylglycerol molecules are present which are ______ at _______ temperature (25C).

Answer 7

oils
liquid
room

Question 8

differentiate fats from oils

form
composition
melting point
source

Answer 8

fats
Solid at RT
More SFA than UFA
Higher
Animals

oils
Liquid at RT
More UFA than SFA
Lower
Plants, Fish

Question 9

GOOD FAT VS BAD FAT

SFA (Good or Bad? and Why)
MUFA (Good or Bad? and Why)
PUFA (Good or Bad? and Why)

Answer 9

SFA : Bad, High risk of Heart Disease
MUFA : Good, Low risk of Heart Disease; Low risk of Breast Cancer
PUFA : Bad and Good, Low risk of Heart Disease; High risk of Breast Cancer

Question 10

OMEGA 3 VS OMEGA 6

Omega 3 ( source and benefits)
Omega 6 (source and benefits)

Answer 10

Omega 3 : Cold water fishes | Low incidence of Heart Disease despite high-fat diet

Omega 6 : Plant Oils | High incidence of Heart Disease if high-fat diet

Question 11

CHEMICAL REACTIONS

Answer 11

● Esterification or Dehydration Synthesis
● Hydrolysis
● Saponification
● Hydrogenation
● Oxidation

Question 12

What is Hydrolisis

Answer 12

● Triacylglycerol is split by water and acid (H+ or enzyme catalyst)
● Produce Glycerol and 3 Fatty acids
● Reverse Esterification

Question 13

Differentiate Acidic and Basic Condition

Answer 13

● Acidic Condition - hydrolysis product of glycerol and fatty acid
● Basic Condition - hydrolysis product is glycerol and fatty acid salts

Question 14

What is Saponification

Answer 14

● Triacylglycerol undergoes hydrolysis with a strong base and is split into glycerol and salts of fatty acids.
● The salts of fatty acids are “soaps”
● Chemical reaction used to make soaps.

Question 15

What is Hydrogenation

Answer 15

● Unsaturated compounds react with H2
● Ni (Nickel) or Pt (Platinum) are Catalysts
● C=C bonds -> C-C bonds
○ Double bonds (UFA) break and
become single bonds (SFA).
● Converts cis double bonds to trans double bonds.

Question 16

have ill effects on blood chemistry similar to those of Saturated Fatty Acids.

Answer 16

Trans fatty acids

Question 17

What is Oxidation

Answer 17

● C=C double bonds present in Unsaturated Fatty Acids are subject to oxidation with Oxygen (from Air).
● Results to short chain Aldehydes.
● Further oxidation will form short chain carboxylic acids.

Question 18

What are membrane lipids

Answer 18

Lipids that are structural components of cell membrane.
○ Up to 80% of the mass of the cell membrane can be lipid material.
○ The rest is primarily proteins.

(1) Phospholipid
- Glycerophospholipids
- Sphingophospholipids
(2) Cholesterol
(3)Sphingoglycolipids
- Cerebrosides
- Gangliosides

Question 19

Most abundant type of membrane lipid.

Answer 19

PHOSPHOLIPIDS

Question 20

What does Phospholipids contain

Answer 20

contains 1 or more fatty acids, a platform molecule, and a phosphate group with an alcohol.

Question 21

What is Sphingophospholipids

Answer 21

Contains a fatty acid and a carbohydrate component attached to a sphingosine.

Question 22

Define Cholesterol

Answer 22

● C27 (carbon) steroid molecule.
○ Composed of 27 carbon linkages.
● Component of cell membranes and precursor for other steroid based lipids.

Question 23

Lipids that stabilize and disperse water-insoluble materials in aqueous solution

Answer 23

EMULSIFICATION LIPIDS

Question 24

Two types of Bile Acids

Answer 24

Cholic Acid
Deoxycholic Acid

Question 25

What is Bile Acids

Answer 25

○ One derivative of cholesterol. ○ It is an emulsifying agent that facilitates the absorption of dietary lipids in the intestine.

Question 26

Regulatory lipids that act in the tissue where they are synthesized or at the other locations after transport via the bloodstream.

Answer 26

MESSENGER LIPIDS

Question 27

Types of Messenger Lipids

Answer 27

Steroid Hormones - Sex Hormones - Adrenocorticoids Eicosanoids - Prostaglandins - Thromboxanes - Leukotrienes

Question 28

female sex hormones; synthesized in the ovaries and adrenal cortex.

Answer 28

Estrogen

Question 29

male sex hormones; synthesized in the testis and adrenal cortex.

Answer 29

Androgens

Question 30

pregnancy hormones; synthesized in the ovaries and placenta.

Answer 30

Progestins

Question 31

control the balance of Na+ and K+ ions in cells and body fluids.

Answer 31

Mineralocorticoids

Question 32

control glucose metabolism and counteract inflammation.

Answer 32

Glucocorticoids

Question 33

involved in many regulatory functions in the body.

Answer 33

Prostaglandin

Question 34

promote the formation of blood clots by promoting platelet aggregation.

Answer 34

Thromboxane

Question 35

found in leukocytes and are associated with various inflammatory and allergic responses.

Answer 35

Leukotriene

Question 36

What are biological waxes

Answer 36

Water insoluble, water repellant lipids with protective coating and lubricating functions.