3.5 Lipids Flashcards
What are lipids?
- diverse group of compound
- insoluble in water, soluble in organic solvents eg. ethanol
What elements do lipids contain?
carbon, hydrogen and oxygen
What are some types of lipids?
waxes, steroids, cholesterol
- triglycerides are the most common (true/neutral fats)
What is the role of lipids?
- major energy source (twice carbohydrates) about 38kJ/g
- heat insulation (mammals, adipose tissue underneath the skin reduces heat loss)
- protection (adipose tissue around delicate organs acts as a cushion against impacts)
Where are lipids stored in the body?
Adipose tissue
What do lipids consist of?
One glycerol, 3 fatty acids
What is a condensation reaction in terms of lipids?
Loss of 3h20 (in fatty acids when they join to the glycerol)
What bond is formed in a condensation reaction making a triglyceride?
Ester bonds
What is the main distinction of a saturated bond?
No double bonds between carbon atoms
What is the main distinction of a mono-unsaturated bond?
One double bond between carbon atoms
What is the main distinction of a poly-unsaturated bond?
More than one double bond between carbon atoms
- causes the molecule to bend
- liquid at room temperature
What is the structure of a phospholipid?
. CH2COO —- Fatty acid
|
CH2COO —- Fatty Acid
|
Phosphate—-CH2
What are the components of the fatty acid side of the phospholipid?
non polar, long chain hydrocarbons,
hydrophobic (repels H2O)
What are the components of the phosphate side of the phospholipid?
charged end of molecule (polar), hydrophilic (attracts H2O)
What is the visual structure of a glycerol molecule?
. H
|
H–C–O–H
|
H–C–O–H
|
H–C–O–H
|
H
