Lipids Flashcards
Name 3 functions of lipids.
Energy storage, thermal insulation and structural components
What’s the most common type of lipid called?
Triglycerides
What are triglycerides composed of?
3 fatty acids and a glycerol molecule
What bonds form when condensation reactions occur between glycerol and the fatty acids?
A condensation reaction removes water from between the glycerol and fatty acids to form ester bonds.
How many ester bonds are formed in triglyceride?
3
What are fatty acids structural features?
A carboxyl group -COOH and R variable group
Describe saturated fatty acids structural features.
They have the max number of hydrogen atoms with no double bonds. They are straight chains which gives them the ability to tightly pack together. They have strong intermolecular forces this results in being solids at room temperature
Describe unsaturated fatty acids.
Less than the max number of hydrogen atoms. They have double bonds which gives them a kinked structure so they do not pack tightly together. They have weak intermolecular forces which gives them the tendency to be liquid at room temperature due to the low melting point.
What does monounsaturated mean?
One double bond
What does polyunsaturated mean?
More than one double bond.
How does a kinked structure affect its chemical properties?
Kinks prevent the unsaturated hydrocarbon chains packing closely together. Increasing distance between molecules weakens intermolecular forces.
How many H20 molecules are released from a triglyceride after a condensation reaction?
3H2O
How are phospholipids similar to triglycerides?
One of the fatty acids is replaced by a negatively charged phosphate group
What is cholesterol?
A short lipid molecule, made in the liver from unsaturated fats
What makes cholesterol so important?
They are vital components of cell membranes as well as acting as sex hormones. Bile salts which help with lipid digestion are formed from cholesterol.
