Lipids Flashcards
What are lipids?
Biological molecules soluble only in organic solvents such as alcohols.
What are the two types of lipids?
- Saturated lipids
- Unsaturated lipids
What characterizes saturated lipids?
They contain only carbon-carbon single bonds.
Where are unsaturated lipids typically found?
In plants.
What do unsaturated lipids contain?
Carbon-carbon double bonds.
What is the melting point comparison between saturated and unsaturated lipids?
Saturated lipids have a higher melting point than unsaturated lipids.
Why are saturated lipids solid at room temperature?
They are more compact and can pack closer together.
What are the properties of lipids?
- Waterproof due to hydrophobic fatty tails
- Compact and better gram-for-gram energy release than carbohydrates or proteins
- Non-polar and insoluble in water
- Conduct heat slowly, providing thermal insulation
What are triglycerides composed of?
One molecule of glycerol and three fatty acids.
What type of bonds are formed in triglycerides?
Ester bonds formed in condensation reactions.
What is the role of triglycerides in cells?
They are used as energy reserves.
What distinguishes phospholipids from triglycerides?
One fatty acid is substituted by a phosphate-containing group.
What are the characteristics of the phosphate heads and fatty acid tails in phospholipids?
- Phosphate heads are hydrophilic
- Fatty acid tails are hydrophobic
What structure do phospholipids form in the cell membrane?
A bilayer.
Fill in the blank: Saturated lipids only contain ______ bonds.
carbon-carbon single
