Membrane structure

Imagine your body is like a house with walls and doors that let some things in and keep others out. Your cells have something like walls called membranes that surround them and help them work properly.

These membranes are made up of tiny building blocks called phospholipids, which look like two long tails with a round head in the middle. The tails are made of oily substances that don't like to mix with water, while the head is a water-loving molecule.

These phospholipids are arranged in a special way to make the membrane. They line up tail-to-tail with their heads facing outwards. This creates a barrier that only lets certain things in and out of the cell.

The membrane also has proteins and other molecules embedded in it that act like doors and windows. Some of the proteins help transport nutrients into the cell, while others act like sensors that detect signals and trigger responses.

Overall, the membrane structure is crucial for the cell's survival and functions like a protective layer that keeps the good stuff in and the bad stuff out.