Download Lipids Lesson Plan

Lesson Plan – Lipids (SBI4U)
Curriculum Expectations:
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B2.3: construct and draw three-dimensional molecular models of important biochemical
compounds (lipids)
B3.2: describe the structure of important biochemical compounds (lipids) and explain their
function within cells
B3.3: identify common functional groups within biological molecules and explain how they
contribute to the function of each molecule
Lesson
Structure of Lipids
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Elemental composition & description of basic properties
Energy-rich, hydrophobic, thermoregulation, building blocks for membranes & hormones
5 types of lipids: fatty acids, fats, phospholipids, steroids, waxes
Fatty Acids & Fats
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Molecular model kit: construct a short fatty acid chain
Make a glycerol model and ask for volunteers to link 3 fatty acids to glycerol to make a
triglyceride (dehydration synthesis)
Demonstrate saturated vs unsaturated fats (kink) & explain significance
o Saturated: obtained from animals, solid at room temperature (butter, lard, yogurt, milk)
o Unsaturated: obtained from plants, liquid/oil at room temperature
 Monounsaturated fats: olives, rapeseed, nuts, avocados and their oils
 Polyunsaturated fats: omega-6 (sunflower seeds, sesame, walnuts, corn and
their oils) & omega-3 (salmon, mackerel, herring, trout, soybean, flax seed and
their oils)
o Ask question: which fat is healthier & why? (Answer: least to most healthiest is
saturated, monounsaturated, omega-6, omega-3 (heart-healthy))
o “trans fat free” labels may not mean 0g of trans fat! It may have less than 0.5g
o Applies to other nutrient facts too (e.g. calorie free means less than 5 calories per
serving)
Phospholipids
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Draw structure & compare with fat
Hydrophobic sand in water demonstration
Describe significance of polarity (amphipathic molecule) in terms of cell membrane
Steroids
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Similar to phospholipids (hydrophobic & hydrophilic properties)
Cholesterol/phytosterol  fluidity of cell membrane
Cholesterol  vitamin D; too much cholesterol  atherosclerosis  heart attack
Sex hormones (estrogen, testosterone) & anabolic steroids (mimics testosterone; side effects
include high blood pressure, reduced growth in youth, depression, suicidal tendencies, change
in sex hormone levels)
Testosterone vs estradiol molecular structure and stability
Waxes
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Long fatty acid chains linked to alcohols/carbon rings
Serve as protection from predators for fruits and leaves (cutin)
Also found on feathers of birds & furs of some animals acting as a water repellent
Copy table (pg. 37 textbook)