BIOLOGICALLY IMPORTANT MACROMOLECULES - LIPIDS. LIPIDS Fats Composed of carbon, hydrogen and oxygen...
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Transcript of BIOLOGICALLY IMPORTANT MACROMOLECULES - LIPIDS. LIPIDS Fats Composed of carbon, hydrogen and oxygen...
BIOLOGICALLY IMPORTANT MACROMOLECULES - LIPIDS
LIPIDS
Fats
Composed of carbon, hydrogen and oxygen- Fewer oxygen, greater carbon and hydrogen
Hydrophobic due to increase in C-H bonds and decrease in O-H bonds
LIPIDS
FUNCTIONS OF LIPIDS:
- Efficient energy storage molecules due to many C-H bonds; provide longer-term energy and processed after carbohydrates are used up
- Insulate against heat loss- Protective cushion for organs- Part of cell membranes- Water-repellent coat for fur, feathers and leaves
LIPIDS
Monomer: hydrocarbon
Formation: hydrocarbons link together to form long chains that can vary in length (~12-24 carbons long)
LIPIDS
TYPES OF LIPIDS:
- Fatty Acids- Glycerides- Phospholipids- Waxes- Steroids
LIPIDS - FATTY ACIDS
Long hydrocarbon chains with a carboxylic acid group at one end
May be saturated or unsaturated
LIPIDS – FATTY ACIDS
SATURATED FATTY ACIDS- No double bonds between carbon atoms- Naturally more linear- Typically solid at room temperature- Linked to heart disease in humans
LIPIDS – FATTY ACIDS
UNSATURATED FATTY ACIDS- At least one double bond between carbon atoms
Monounsaturated: one double bondPolyunsaturated: two or more double bonds
*** Cannot be synthesized by humans
- Naturally have a bend (cis double bonds) which alter the physical properties and behaviour in the body
- Generally liquids- Can reduce the risk of heart disease
LIPIDS – FATTY ACIDS
LIPIDS - GLYCERIDE
Formed when fatty acids join a glycerol backbone through CONDENSATION/DEHYDRATION SYNTHESIS reactions between the carboxylic acid group of the fatty acid and the hydroxyl group of the glycerol forming an ESTER linkage (ester functional group)
LIPIDS - GLYCERIDE
May have monoglycerides, diglycerides or triglycerides
LIPIDS - GLYCERIDE
Function:- Most fats we eat- How the body stores fats
LIPIDS – TRIGLYCERIDE
HYDROGENATION: chemical addition of hydrogen to unsaturated fatty acids of triglycerides to produce saturated fats- Converts remaining double bonds from cis fats to trans fats
LIPIDS - PHOSPHOLIPIDS
Glycerol with two fatty acids and a phosphate group attached to the glycerol backbone
- Phosphate is attached to an R group that varies in composition and defines the type of phospholipid
LIPIDS - PHOSPHOLIPIDS
When phospholipids interact, they align themselves so that their polar head groups stay together and their nonpolar fatty acid tails stay together
Function: form a double layer (bilayer) that forms cell membranes
LIPIDS - WAXES
Long chain fatty acids joined to alcohol or carbon rings
Solid at room temperature
Function: water proof coatings (Ex: on leaves and feathers)
LIPIDS - WAXES
Function:
- Water proof coatings (Ex: on leaves and feathers)
- Various plant functions (Ex: leaf, skin, fur and feathers coating)
- Various animal functions (Ex: earwax, beeswax, lanolin, etc.)
LIPIDS - STEROIDS
Four fused hydrocarbon rings with several different possible functional groups
LIPIDS - STEROIDS
Function:- Cholesterol (adds rigidity to membranes)- Hormones (Ex: testosterone, estrogen, progesterone,
adrenaline)- Inflammation treatment- Vitamin D- Can cause heart disease
Made by mammals and acquired through diet