Triglycerides

What are lipids made of?

Lipids are organic compounds made of carbon, hydrogen, and oxygen.

What is a characteristic group that all lipids contain?

A high proportion of CH2 groups.

What additional element do phospholipids contain?

Phosphorus.

How soluble are lipids in water compared to organic solvents?

Lipids have low solubility in water and high solubility in organic solvents.

What determines whether triglycerides are classified as fats or oils?

The size of the triglyceride molecule; larger molecules are fats, smaller are oils.

What are the components of a triglyceride?

A triglyceride is made from glycerol and three fatty acids.

What reaction combines glycerol with fatty acids to form triglycerides?

A condensation reaction.

What type of bonds bind fatty acids to glycerol in triglycerides?

Ester bonds.

How are triglycerides broken down?

Through hydrolysis with the insertion of three molecules of water.

What does the letter 'R' represent in fatty acid structures?

A variable group containing a chain of between 4 and 24 carbon atoms.

How do the lengths of hydrocarbon chains affect the state of lipids at room temperature?

Longer chains are more likely to be solid (fats), while shorter chains form liquids (oils).

What is one efficient function of triglycerides?

They are efficient energy storage molecules.

How much energy does 1 g of fat provide compared to carbohydrates?

1 g of fat provides about 38 kJ energy, while 1 g of carbohydrate provides about 17 kJ energy.

What role do triglycerides play in thermal insulation?

They serve as good thermal insulators.

Why do some animals use oil on their fur or feathers?

To provide waterproofing because fats are hydrophobic and repel water.

How do triglycerides contribute to buoyancy in aquatic animals?

Because fats are less dense than water.