Active transport

Lesson Objectives• All will be able to define active transport

• Most will be able to explain in detail how active transport happens

• Some will be able to give example and suggest reasons why active transport is important

Draw an animal and plant cell(remember to label all the different organelles!)

Movement in and out of cellsHow do substances get in and out of cells?

True or false?

1. Osmosis involves the movement of water2. Diffusion requires energy3. Diffusion occurs in liquids, solids and gases4. Osmosis requires a semi permeable membrane5. All molecules can pass through a semi permeable

membrane6. A hypotonic solution is a strong solution7. A hypertonic solution is a strong solution8. If water moves into a plant cell it will burst9. Water is produced by actively respiring cells10. Osmosis and diffusion will continue until dynamic

equilibrium is reached

Jot down a quick definition of osmosis and diffusion

Active transport

• Another way of getting molecules into cells

• Animal and plant cells cannot rely on diffusion alone to get the molecules they need.

• What if they need molecules that are in a higher concentration inside the cell than outside?

What is active transport?

As the name suggests, active transport requires energy from the cell, which is made available by respiration.

During active transport, protein carriers in the cell membrane ‘pick up’ particles and move them against the concentration gradient.

What is needed for active transport?

• Unlike osmosis and diffusion energy and a carrier protein is needed to transport molecules across the cell membrane

Key words: Active transport; Energy; Carrier protein

Active transport

• Stick the pictures showing active transport in your book, label and explain what is happening at each stage:

• Key words:– Carrier protein, energy (ATP), membrane,

high concentration, low concentration, mitochondria, against concentration gradient

Hwk: Active transport

• How do animals and plants use active transport?

• Use text books to research ways which active transport is used

Diffusion, Osmosis and Active Transport compared

Diffusion OsmosisActive Transport

Movement by concentration

Molecule transported

Energy used

Carrier protein

Diffusion, Osmosis and Active Transport compared

Diffusion OsmosisActive Transport

Movement by concentration From high to low From high to low From low to high

Molecule transported Any Water Any

Energy used No No Yes

Carrier protein No No Yes