Why are eggs high in colesterol?

Fowl eggs and caviar are high in cholesterol, but they have a low fat content (saturated fat being very low). One Hen's egg has 3.5 grams of fat to approx 156 grams of cholesterol. Caviar contains only 2.5-5 grams of fat, but has 95 grams of cholesterol per serving. What makes them high in cholesterol?