LIPIDSAKA: FATS

LIPIDS- large nonpolar organic molecules

•18%-25% of body weight

•fewer covalent bonds

•fat-marbled meats, egg yolks, milk, oils, waxes

•Most lipids are insoluble in water but dissolve in other lipids and alcohol, acetone (NONPOLAR)

Fatty Acids -unbranched C chains that make up most lipids

• long carbon chains with a carboxyl group at the end (COOH)• carboxyl end is polar and thus hydrophilic-attracted to water•hydrocarbon end is non-polar and thus hydrophobic- water fearing

• Saturated fatty acid-a fatty acid where all the carbon to carbon bonds are single bonds

•Unsaturated fatty acid- there is at least on carbon to carbon double bond

•Higher ratio of carbon and hydrogen atoms to oxygen atoms• causes them to have more carbon to hydrogen

bonds which store more energy….hence fats having a higher caloric value

NEUTRAL FATS (TRIGLYCERIDES)

•BUILDING BLOCKS•3 Fatty acids•Glycerol

•most common in the body • Concentrated sources of energy• adipose tissue insulates and protects organs

http://drs.yahoo.com/S=96062883/K=triglyceride/v=2/l=IVI/*-http://www.brooklyn.cuny.edu/bc/ahp/SDgraphics/PSgraphics/Triglyceride.GIF

http://drs.yahoo.com/S=96062857/K=adipose+tissue/v=2/SID=e/l=II/R=1/*-http://images.search.yahoo.com/search/images/view?back=http%3A//images.search.yahoo.com/search/images%3Fsrch=1%26p=adipose%2Btissue%26ei=UTF-8%26n=20%26fl=0&h=828&w=1152&imgurl=education.vetmed.vt.edu/Curriculum/VM8054/Labs/Lab5/IMAGES/Brown%2520adipose%2520Tissue%2520photo%2520WITH%2520LABEL%2520copy.jpg&name=Brown+%3Cb%3Eadipose%3C/b%3E+%3Cb%3ETissue%3C/b%3E+photo+WITH+LABEL+copy.jpg&p=adipose+tissue&rurl=http://education.vetmed.vt.edu/Curriculum/VM8054/Labs/Lab5/Examples/exbrnfat.htm&no=1&tt=440

•SOLID: (animal fats)•Saturated: carbons have single bonds

•LIQUID: (plant oils)•Unsaturated: carbons have double or triple bonds

http://drs.yahoo.com/S=96062883/K=saturated+fats/v=2/l=IVI/*-http://telstar.ote.cmu.edu/Hughes/tutorial/cellmembranes/img/saturated.jpg

PHOSPOLIPIDS

• Important in cell membranes – allows them to be selective

• POLAR HEAD – attracts and interacts with water and ions (hydrophilic)

• NONPOLAR TAILS- ‘hydrophobic’

Waxes-• Composed of a long fatty acid chain joined to

a long alcohol chain•Wax can be found on the outside of plants to

prevent water loss especially through leaves• Can also be found in your ears where it

prevents microorganisms from entering the ear canal

STEROIDS

•Four interlocking rings

•Structure differs from other fats

•Made largely of H and C atoms

CHOLESTEROL• is most important molecule in steroids•meat, eggs, cheese•Certain amount made in liver•Found in ALL cell membranes •Provide rigidity •Facilitates communication between cells

•Particularly abundant in brain

•Used to form sex hormones, cortisol (stress hormone), bile salts, and vitamin D

ATHEROSCLEROSISdeposit of FAT in artery walls

ATERIOSCLEROSIShardening of arteries

http://drs.yahoo.com/S=96062883/K=arteriosclerosis/v=2/l=IVI/*-http://www.terra.es/personal2/rmm00005/Arterioesclerosis2.gif

OLIVE ‘OYL’

‘POLLY’ UNSATURATED

HOW DO WE MAINTAIN HOMEOSTATIS?

•Omega-3 Fats (Fish, walnuts)• safflower, corn,

sunflower and soybean oils