Highlight: Lipids contain more energy per gram than carbohydrates and proteins, making them efficient energy storage molecules.

Definition: Fats are lipids that are solid at room temperature, while oils are liquid at room temperature.

Example: Glycerol (C₃H₈O₃) combines with fatty acids to form more complex lipids.

Definition: Phospholipids are modified triglycerides where one fatty acid chain is replaced with a phosphate group.

Highlight: Phospholipids have both hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails, crucial for cell membrane formation.

Example: When mixed with water, phospholipids can form structures called micelles, with heads facing water and tails clustering together.

Definition: Primary structure refers to the sequence of amino acids in a polypeptide chain.

Vocabulary: Alpha helix - A spiral structure held together by hydrogen bonds. Beta strand - An almost straight chain structure that can form pleated sheets.

Highlight: The tertiary structure creates unique active sites in enzymes through various types of bonds between R groups.