Book 33, Question 26
What is mammal milk made of?
Milk is a drink that mothers make to feed their babies.
It is mostly water, but it also has fat for energy, protein for growing, sugar called lactose for fuel, and minerals like calcium for bones. A mother’s body builds milk from the food and water she takes in. Babies of every mammal drink milk at the start of life, and it gives them everything they need.