Fats and Oils

Fats

• What are they also known as? (two names)

• What molecules are they composed of? How many of each?

• What are their bonds called? How do these bonds form?

AKA: Triaglycerols or triglycerides

Composed of: 1 glycerol and 3 fatty acids

Bonds: Ester bonds, formed through dehydration synthesis

Fatty Acids

• What are their two main components?

A long hydrocarbon chain

A carboxyl group (-COOH) at the end

Saturated fatty acids

• What bonds do saturated fatty acids have?

• Why are they called “saturated”?

• What form are they at room temperature?

• What substance are saturated fatty acids often found in?

Bonds: Single bonds only

They are called “saturated” because they are fully saturated with hydrogen

Solid at room temp.

Often found in animal fats (e.g., lard)

Unsaturated fatty acids

• What bonds do unsaturated fatty acids have?

• Why are they called “unsaturated”?

• What form are they at room temperature?

• What are the two types of unsaturated fatty acids?

• Bonds: At least one double bond

• They are called “unsaturated” because they are not fully saturated with hydrogen atoms

• Liquid at room temp. (Oil)

• Two types:

(1) Monounsaturated (one double bond) fatty acids

(2) Polyunsaturated (multiple double bonds) fatty acids

Cis fats

• Definition

• Shape (does it have a bend?)

• Form at room temperature?

Definition: Unsaturated fat where hydrogens are on the same side of the double bond

Shape: Has a bend

Liquid at room temperature

Trans fats

• Definition

• Shape (does it have a bend?)

• Form at room temperature?

• Definition: Unsaturated fat where hydrogens are on opposite sides of the double bond.

• Shape: Does not have a bend

• Solid at room temperature, usually

Biological role of fats

• What is the main function of fats in organisms?

• Where is fat stored in animals?

• Where is fat stored in plants? What does it do?

Main function: Long-term energy storage

Animals: Stored in fat cells, “adipocytes”

Plants: Stored in seeds, providing seedlings with energy.