How do plants taken in water from the

How do plants taken in water from the Soil?

Root Hair Cells • Roots do more than just anchor the plant in the ground, they take up water and mineral salts from the soil. • The surface of the cells have specialised root hair cells with long thin extensions that reach into the surrounding soil. • The root hairs provide a large surface area for substances to enter the root.

Osmosis • Water enters the root hair cells by osmosis. • In this process, water moves across a partially permeable membrane. (A membrane that only certain substances can pass through) from a region where it is in a higher concentration to a region of a lower concentration.

Osmosis is a special case of diffusion. It is the net movement of water across a selectively permeable membrane from a high concentration to a low concentration. Selectively permeable membrane ? ? ? The cell membrane has very small holes in it. Small molecules can pass through, but larger ones cant. We say it is selectively permeable.

Why is osmosis important? 1. Plants rely on the movement of water through them: 2. Water always moves to areas of lower water concentration. 3. Root hairs take in water from the soil by osmosis.

Comparing osmosis and diffusion Osmosis Diffusion Particles move randomly Water moves down a concentration gradient Substances move from an area of high concentration to low concentration Involves a partially permeable membrane Doesn’t require a membrane Needs water for movement Doesn’t need water for movement Does not require cell energy for movement