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Flashcards in ME03 - Lipid Significance Deck (58):
1

Importance of Lipids

_fats, oils, steroids, waxes

2

Common Physical proprties of Lipids

Relatively insoluble in water soluble in nonpolar solvents

3

Important Dietary constituents

fat-soluble vitamins Micronutrients long chain omega-3 fatty acids

4

Where are lipids stored in the body

Adipose Tissue

5

Clinical Diseases that Involve Lipids

obesity, diabetes mellitus, and atherosclerosis

6

Classification of Lipids

1. Simple lipids A. Fats- Triglycerols, Oils B. Waxes Do not have triglyceride ester of three fatty acids Fatty acid and alcohol esters 2. Complex lipids A. Phospholipids - lipid with phosphate grp Glycolipids (glycosphingolipids) - Other complex lipids - Lipoproteins 3. Precursor and derived lipids fatty acids, glycerol, steroids, other alcohols, fatty aldehydes, ketone bodies, hydrocarbons, lipid-soluble vitamins and micronutrients, and hormones

7

Fatty Acids are Aliphatic Carboxylic Acids, True or False

TRUE

8

Transport form in the plasma

Free Fatty Acids

9

Lipids that contain no double bonds

Saturated, Example: Acetic Acid (CH3COOH), Butyric(4) Valeric (5) Caproic (6) Lauric (12) Myristic (14) Palmitic (16) Stearic (18)

10

Lipids containing one or more double bonds

Unsaturated Example: Monounsaturated Polyunsaturated Eicosanoids - Eicosa (20-carbon) polyenoic fatty acids Prostanoids, Leukotrienes (LTs), Lipoxins (LXs)

11

Unsaturated fatty acids has a higher melting point than saturated fatty acids

TRUE

12

C16:0 or 16:0

Palmitic, No. of C = number of double bonds

13

C18:2 (9,12) w-carbon (methyl carbon)

Linoleic acid

14

C18:3 (9,12,15)

Linolenic acid

15

What are essential Lipids

Linoleic acid; Linolenic Acid (ADEK)

16

Essential Amino Acids needed since Linoleic and Linolenic Acid cannot be made by the human body

Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, Valine + (Arginine for infants)

17

Is there such thing as an essential carbohydrates?

NO, THERE'S NONE.

18

Types of Geometric Isomerism

cis- If the acyl chains are on the same side of the bond (oleic acid) Double bonds in fatty acids Trans- If the acyl chains are on opposite sides (elaidic acid)

19

Most naturally occuring unsaturated fatty acid

Unsaturated fatty acids that have CIS-DOUBLE BONDS

20

Disease associated with trans and saturated fatty acids

Atherosclerosis

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Trans double bonds are ____________

Unnatural. It causes decreased fluidity (Ex. Margarine)

22

Physical and Physiologic Properties of Fatty Acids

More saturated = More solid at body temperature Polyunsaturated= Liquid to below zero dec celsius membrane lipids| Hibernators

23

What are Omega 3 Faty Acids

_-linolenic (ALA) - Found in plant oils eicosapentaenoic (EPA) - found in fish oil docosahexaenoic (DHA) - found in fish and algal oils

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Clinical Significance of Omega 3 Fatty Acids

anti-inflammatory effects promoting the synthesis of less inflammatory prostaglandins and leukotrienes cardiovascular disease Cancer Rheumatoid arthritis Alzheimer disease

25

Main storage forms of fatty acids

Triglycerides (C1 and C3 of glyceril are not identical when viewed in three dimensions)

26

Precursor of Phospholipids, Influence membranes and acts in Signalling

Phosphatidic Acid

27

Glycerophospholipids containing choline

Lecithins (phosphatidylcholine) most abundant phospholipids of the cell membrane

28

Why is Choline important?

Important in Nervous transmission, as acetylcholine, and as store of labile methyl groups

29

Phospholipid that acts as surfactant

Dipalmitoyl Lecithin contains Type II alveolar cells preventing adherence, due to surface tension, of the inner surfaces of the lungs

30

Clinical Significance of Dipalmitoyl lecithin as surfactant

Respiratory Distress Syndrome

31

Ethanolamine or serine, respectively, replaces choline

_Phosphatidylethanolamine (cephalin) and phosphatidylserine

32

Plays a role in apoptosis (programmed cell death)

_Phosphatidylethanolamine (cephalin) and phosphatidylserine

33

Found in the outer leaflet of the cell membrane lipid bilayer, lipid rafts, and myelin sheath

Sphingomyelins

34

Function of Sphingomyelins

Cell signaling and apoptosis

35

Phopholipid found only in mitochondria

Phosphatidylglycerol

36

Gives rise to Cardiolipin

Phosphatidylglycerol

37

Alterations in functions of Phosphatidylglycerol can result to

heart failure and hypothyroidism and aging

38

Gives rise to Lysolecithin important in the metabolism and interconversion of phospholipids found in oxidized lipoproteins

Lysophosphatidylcholine

39

Clinical Significance of Lysophosphatidylcholine

Atherosclerosis

40

Lipids with an attached carbohydrate or carbohydrate chain Widely distributed in every tissue of the body, particularly in nervous tissue; Occur partly in the outer leaflet of plasma membrane Contributes to Glycocalyx

Glycolipids

41

Major glycosphingolipid of brain and other nervous tissue

_Galactosylceramide

42

Galactosylceramide is converted to ______ which is present in high amounts in MYELIN

Sulfatide

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Resembles galactosylceramide, head group is glucose rather than galactise

Glucosylceramide

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Complex glycosphingolipids derived from glucosylceramide

Gangliosides

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Function of Gangliosides

GM1 - Function in cell-cell recognition and communication and as receptors for hormones and bacterial toxins (cholera)

46

Predominant simply glycosphingoloid of extraneural tissues

Glucosylceramide

47

What is the precursor of Steroids

Cholesterol

48

Precursor of large number of employed steroids includes;

Bile Acids, Adrenocortical Hormones, Sex hormones, Vitamin D & Cardiac Glycosides

49

What is the precursor of Vitamin D

Ergosterol

50

Not steroids Related because they are synthesized, like cholesterol from Fivecarbon isoprene units Rubber, camphor, the fat-soluble vitamins A, D, E, and K, and _-carotene (provitamin A)

Polyprenoids

51

Polyprenoid that has Respiratory chain in mitochondria

Ubiquinone

52

Polyprenoid that takes part in glycoprotein synthesis

Dolichol

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Auto-oxidation of lipids Responsible for rancidity of foods Damage to tissues in vivo Cancer, inflammatory diseases, atherosclerosis, and aging

Lipid Peroxidation

54

Molecules that have unpaired valence electrons Reactive oxygen species (ROS)

Free Radicals

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Chain reaction providing continuous supply of ROS

Initiation - Propagation - Termination

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2 classes of Antioxidants

1. Preventive antioxidants Catalase| EDTA | DTPA | Glutathione peroxidase 2. Chain-breaking antioxidants Superoxide dismutase | vitamin E

57

Why are LIPIDS insoluble in water

Predominance of nonpolar (hydrocarbon) groups

58

Part of the molecule is hydrophobic, or water insoluble; and a part is hydrophilic, or water soluble

AMPHIPATHIC - Micelles, Liposomes