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Lipids Lipids

A Type of Organic MoleculeA Type of Organic Molecule

-Fats, Oils, Waxes and -Fats, Oils, Waxes and SteroidsSteroids

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Not soluble in HNot soluble in H22O but are soluble in oils.O but are soluble in oils.

More energy in lipids than in carbohydratesMore energy in lipids than in carbohydrates Made up of C, H, O but very little OMade up of C, H, O but very little O

Lipids Lipids

23_541

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Triglyceride: FatsTriglyceride: Fats1 glycer1 glycerolol + 3 Fatty acids + 3 Fatty acids

glycerol and fatty acids (hydrocarbon chains) hooked glycerol and fatty acids (hydrocarbon chains) hooked together by dehydration synthesis (condensation rxn)together by dehydration synthesis (condensation rxn)

Glycerol Hydrocarbon chain (non polar)Glycerol Hydrocarbon chain (non polar)

http://www2.nl.edu/jste/lipids.htm

*Draw the molecule in the space provided*Draw the molecule in the space provided

Glycerol Hydrocarbon chain (non polar)Glycerol Hydrocarbon chain (non polar)

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When drawing hydrocarbons it is often easier and When drawing hydrocarbons it is often easier and quicker to draw a kinked line where each kink quicker to draw a kinked line where each kink represents a carbon. represents a carbon.

The angled appearance of the bonds is also a The angled appearance of the bonds is also a better representation of its actual structure.better representation of its actual structure.

C C CC C C

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PhospholipidPhospholipidSame structure as triglyceride but with 1 phosphate Same structure as triglyceride but with 1 phosphate

group group

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2 types of fat on 2 types of fat on hydrocarbon tailhydrocarbon tail

Saturated Saturated

A butter sculpture from the North Carolina state fair

Unsaturated fatsUnsaturated fats

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Saturated Fats: Saturated Fats: Has as many H’s as you can getHas as many H’s as you can get Solid at room temperature b/c carbon Solid at room temperature b/c carbon

chains are straight and “stack” up flatchains are straight and “stack” up flat Made by animalsMade by animals

Examples include:Examples include: FatFat LardLard ButterButter

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Triglyceride: FatsTriglyceride: Fats

m.p. 70ºC

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More butter sculpture…More butter sculpture…

Yes, this is made Yes, this is made of butter. of butter.

It’s called “Deep in It’s called “Deep in the heart of the heart of Texas”Texas”

A fine use of A fine use of saturated fat.saturated fat.

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Unsaturated Fats:Unsaturated Fats: Has double bonds, less H’sHas double bonds, less H’s Made by plantsMade by plants Oil (liquid) at room temperatureOil (liquid) at room temperature

m.p. 16ºC m.p. -5ºC

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I. Triglycerides and Fatty Acids

fatty acids:•most have even numbered chains, between 12 and 20 carbons•cis isomer predominates in unsaturated fatty acids•more unsaturation lower melting point

OH

O

O

OH

OH

O

OH

O

stearic acid (18:0)m.p. 70ºC

oleic acid (9-18:1)an -9 fatty acidm.p. 16ºC

linoleic acid (9,12-18:2)an -6 fatty acidm.p. -5ºC

linolenic acid (9,12,15-18:3)an -3 fatty acidm.p. -11ºC

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Steroids Steroids Consist of four interconnected rings of carbonConsist of four interconnected rings of carbon

Cholesterol Cholesterol (type of steroid)(type of steroid) HormonesHormones (type of steroid) (type of steroid)

TestosteroneTestosterone EstrogenEstrogen ProgesteroneProgesterone

H

CH3

CH3

H

H

H

A B

C D

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androgens (male sex hormones)•produced in the testes•responsible for development of male sex characteristics

estrogens (female sex hormones)•produced in the ovaries•responsible for development of female sex characteristics

cortisone hormones•produced in the adrenal cortex•regulate metabolism of carbohydrates, decrease inflammation, involved in reaction to stress

OH

Otestosterone

O

O

progesterone

O

OHO

O OH

cortisone

HO

O

androsterone

HO

O

estrone

O

OHO

HO OH

cortisol

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