A1.1

• Cohesion is when water sticks to itself

• Adhesion is when water sticks to other things

  • Adheres to xylem stem to come from ground to top

  • Transpiration is drawing water from the ground to the top of plants through the xylem

• As leaves release water there is an area of low pressure and low pressure draws water up the xylem

• The water is drawn up because it wants to stick together

• Thinner the vessels, easier for the water to draw up through

• Surface tension is the tendency of water to stick to itself

  • Bigger amount of water trying to take up a smaller amount of space

  • Tension resists breaking apart the hydrogen bonds which forms surface tension

• Polar molecules don't dissolve well in water (hydrophobic)

• Non-polar molecules dissolve well in water (hydrophilic)

• Plasma membrane is hydrophobic

  • Phospholipids have to be hydrophobic

• Enzyme catalyse

  • Speeds up chemical reactions

  • It's not used up in the process

Properties of water

• Buoyancy

• Viscosity

• Thermal conductivity

  • Heat and water is high

  • Air and water is low

• Specific heat capacity