Phospholipids vs SDS

• Phospholipids and SDS are both amphipathic molecules. 
• However, SDS has one hydrophobic tail and one hydrophilic head, while phospholipids have one hydrophilic head and two hydrophobic tails.
• That difference matters: 
• Phospholipids pack tightly and form a stable bilayer, while SDS does not fit well into that structure. 
• Instead, SDS inserts into the membrane and disrupts the interactions between phospholipids, causing the membrane to lose integrity and eventually break apart.