BIO 2: Lipids

Ampiphatic molecules that store energy

Lipids

An amphipath or amphiphile is a molecule that has both polar (hydrophilic) and nonpolar (hydrophobic) parts.

What are the 4 components of lipids?

1. Polar groups

2. PO3

3. Glycerol

4. Fatty Acid chains

1,2 Hydrophilic kasi polar

3,4 Hydrophobic kasi nonpolar

The only non-polymeric biomolecules

Lipids

What form of lipids naturally occur?

Cis, even number of carbons

Lipids are soluble in ____ and insoluble in ___.

organic solvents; water

What kind of bond does lipids have?

Ester bonds

Hydrolyzable Lipid: 3 Types

1. Biological Waxes
   = simplest hydrolyzable lipids
   = esters from: high MW ROH + 1 fatty acid (RCOOH)
   = hydrophobic, used in water-proofing
   > cosmetic     > food industry (coat)    > plant biology (gabi)

2. TAGs (Triacylglycerol/Triglyceride)
   = most abundant lipid
   = fats/oils
   = 3 FA + 1 glycerol
   > saturated   > unsat

3. Phospholipid
   1. PAGs /Phospoacylglycerol/ Phosphoglyceride
   2. Sphingomyelins)
   = organic derivatives of phosphoric acid with
     >  glycerol/sphingosine  > 2 FA   > phosphate
   = “membrane lipids”

Hydrolyzable Lipid: What is the basic hydrolysis of TAGs?

Saponification

Hydrolyzable Lipid: Saturated vs Unsaturated Fatty Acids

Saturated = linear, no double bonds, solid, animal fats, less reactive (↑C ↑MP) 

Unsaturated = bent cis, with double bonds, liquid, plant oil, (↑double bonds, same #C, ↓MP more prone to breaking)

C=C are e- rich, more reactive, more prone to degradation

Hydrolyzable Lipid: Name all C10-C30 Saturated Fatty Acids

(Ca)rush (La)ng Muna Para Safe Ako,
Baby (Lig)oves (Ce)ute Mo Mahal

Capric Lauric Myristic Palmitic Stearic Arachidic,
Behenic Lignoceric Cerotic Montanic Melissic

Hydrolyzable Lipid: What are fatty acids with 2 or more double bonds?

Polyunsaturated fatty acids (PUFAs)

Hydrolyzable Lipid: What are PUFAs that the body can’t synthesize?

Essential fats PUFAs.

Hydrolyzable Lipid: What are two essential omega-3 and omega-6 PUFAs?

Alpha-linoleic acid = omega-3 = fish

Linoleic acid = omega-6 = plant, soy, nuts

(3,6  are the position of the first C=C)

Hydrolyzable Lipid: What is the chemical process of adding H2 that can reduce the double bonds of unsaturated bonds, hence extending the shelf life?

Hydrogenation (C=C →(Pt)→ C-C)

Hydrolyzable Lipid: The only unsaturated fatty acids that has a linear structure.

Trans fats

Hydrolyzable Lipid: What type of phospholipid forms the principal lipid component of most cell membranes, which is also the 2nd most abundant lipid? 

PAGs, Phosphoacylglycerols, Phosphoglycerides

Hydrolyzable Lipid: 2 Types of PAGs

1. Cephalin
   = Inner leaflet (cytoplasmic side) of the lipid bilayer.
   = Functions:
     > Supports and stabilizes membrane curvature.
     > Plays a key role in blood coagulation pathways.

2. Lecithin
   = Outer leaflet (exoplasmic side) of the lipid bilayer.
   = Functions:
     > Maintains the structure and fluidity of the cell membrane.
     > Aids in the transport and metabolism of lipids.

Hydrolyzable Lipid: What type of phospholipid is a sphingolipid found in animal cell membranes for insulation of nerve fibers?

Sphingomyelin (Myelin sheets)

Hydrolyzable Lipid: Differentiate PAGs, Sphingomyelins, and ceramides in terms of where they’re derived from.

PAGs = derived from glycerol
Sphingomyelins = derived from sphingosine
Ceramides = derived from sphingosine

Hydrolyzable Lipid: Which has both a structural and functional role? Phospholipid or steroid?

Phospholipid

What type of lipids cannot be broken down further into smaller units by aqueous hydrolysis?

Nonhydrolyzable lipids.

What are the 4 types of nonhydrolyzable lipids?

1. Fat-soluble vitamins

2. Eicosanoids

3. Terpenes

4. Steroids

Nonhydrolyzable Lipids: What are the 4 fat-soluble vitamins?

A D E K

found in fruits, veg, fish, liver, and dairy products.

in excess = stored in fat cells

Nonhydrolyzable Lipids: Discuss the functions of Vitamin ADEK.

1. Vit A = retinol, vision

2. Vit D = cholecalciferol, calcium absorption

3. Vit E = tocopherol, anti-oxidant (“Myra E”)

4. Vit K = phylloquinone, helps in blood clotting, immune system

Nonhydrolyzable Lipids: Discuss all 8 vitamin B complexes.

TaRa Na PaPy Bili Fries and Coke

Thiamin Riboflavin Niacin PantothenicAcid Pyridoxine Biotin FolicAcid Cobalamin

1 2 3, 5 6 7, 9, 12
(walang 4 8 10 11)

Nonhydrolyzable Lipids: What is the metal cofactor of Vitamin B12? Cobalamin

Cobalt

Nonhydrolyzable Lipids: Biologically active compounds derived from arachidonic acid.

Eicosanoids

Nonhydrolyzable Lipids: What are the 4 classifications of eicosanoids?

1. Prostaglandins

2. Thromboxanes

3. Prostacyclins

4. Leukotrienes

Nonhydrolyzable Lipids: ___________ blocks COX 1 and 2 enzymes that stops the creation of prostaglandins (pain signaling molecules).

Aspirin and Ibuprofen

Nonhydrolyzable Lipids: Fragrant l ipids composed of repeating units of isoprene (5 carbons). Give 6 types of it.

Terpene

1. Monoterpene 10 C

2. Sesquiterpene 15 C

3. Diterpene 20 C

4. Sesterterpene 25 C

5. Triterpene 30 C

6. Tetraterpene 40 C

Nonhydrolyzable Lipids: Type of triterpene that is the intermediate of cholesterol.

Squalene

Name 5 common terpenes.

Nonhydrolyzable Lipids: Biologically active tetracyclic lipids (3 cyclohexane + 1 cyclopentane)

Steroids

Nonhydrolyzable Lipids: ____ are steroids secreted by endocrine glands, and can be classified as: s*x and adrenal cortical steroids.

Hormones

Lipids naturally self-assemble into organized structures due to their amphipathic nature. Name 3 structures.

1. Micelle

2. Lipid bilayer

3. Vesicle/Liposome

___________- 1-layer spherical aggregates, fatty acid cone shape. Aids in solubilizing hydrophobic substances, particularly in digestion.

Micelle

________ - 2-layer phospholipid with 2 hydrophobic tails face inward. Inverted cone (droplet) shape, cylindrical. Forms the structural basis of biological membranes acting as a selective barrier

Lipid bilayer

____________ - formed by lipid bilayers enclosing an aqueous structure, forming a spherical structure. Cylindrical lipids. Protects the structure of molecule. Serves in intracellular transport and drug delivery.

Liposome

Which among the lipids are the most abundant?

1. TAGs

2. PAGs