FINAL QUIZ QUESTION

As a class, we have claimed that there is starch in potatoes. With your table partners, prove to me that this is true. Petri dishes and potatoes will be given to you. The rest is up to you. Explain the process you used and show me your results.

LIPIDS

Made of Carbon, Hydrogen, and Oxygen

Are Hydrophobic 4 Classes

– Waxes– Steroids– Phospholipids– Fats (Triglycerides)

Waxes

Some act as waterproofing systems– Example- leaves and feathers

Other waxes– Beeswax, earwax

Steroids

Skeleton of interconnected rings of carbon

Examples– Cholesterol- in cell membranes– Sex Hormones (testosterone, estrogen,

etc.)– Chlorophyll in plants– Retinol in our eyes

Cholesterol- A steroid

Phospholipids

Similar to fats but only 2 hydrocarbon chains

Head is composed partly of PHOSPHATE Group (PO4)

very important in cell membrane

Phospholipid

Head-glycerol + phosphate

2 Fatty Acid tails

Fats (aka Triglycerides)

Made of Glycerol + 3 Fatty acids Large hydrocarbon chains (H + C)

Triglyceride ( fat)

How does a triglyceride differ from a carbohydrate?

Store much more energy (more than 2x) Much more difficult to break down

Types of fats

Saturated Unsaturated

– Monounsaturated– Polyunsaturated

A Saturated Fat

Saturated Fats

Carbons bonded to max. # of hydrogens– No double bonds

Solids at room temperature Bacon, grease, lard, butter, cheese,

chocolate

Unsaturated Fats

Carbons not bonded to max # of hydrogens– Some carbons double bonded- chain

becomes kinked (see drawing) Liquid at room temp. (OILS) Vegetable oil, olive oil, peanut oil, fish

oil, etc.