Topic: Active Transport Aim: How do cells move certain molecules against their concentration gradient? Question Molecules have a natural tendency to spread out, will move from crowded area to less crowded area, until balance/equilibrium is reach. Thus, how can the cell in the picture get those molecules from the outside going in, even if it’s already crowded inside?

Answer: Cell needs to put in energy (ATP) to move those molecules inside. Why do cells need to but in energy (ATP)? Because it is more crowded inside. Those molecules do not want to stay inside. Thus, cells need to spend energy to move and keep them inside. This is an example of active transport.

Active Transport cell uses energy actively moves molecules to where they are needed Movement from an area of low concentration to an area of high concentration (Low  High)

What is Active Transport? Cells use energy (ATP) Move molecules against their concentration gradient (push them to even more crowded area) Actively moves molecules to where they are needed high low This is gonna be hard work!! More crowded inside Less crowded outside

3 Types of Active Transport Sodium-Potassium pump Endocytosis Exocytosis

Protein changes shape to move molecules: this requires energy! Active Transport Sodium Potassium Pumps (Active Transport using proteins) 1. Protein Pumps -transport proteins that require energy to do work Example: Sodium / Potassium Pumps are important in nerve responses. Protein changes shape to move molecules: this requires energy!

Active Transport 2. Endocytosis: taking bulky material into a cell Uses energy Cell membrane in-folds around food particle “cell eating” forms food vacuole & digests food This is how white blood cells eat bacteria!

Endocytosis & Exocytosis animations Active Transport 3. Exocytosis: Forces material out of cell in bulk membrane surrounding the material fuses with cell membrane Cell changes shape – requires energy EX: Hormones or wastes released from cell Endocytosis & Exocytosis animations

Check for Understanding Which type of active transport is being shown by the diagram on the right?_________________ Does the cell have to put in energy (ATP) to pull the molecule in? _________

Check for Understanding The diagram on the left shows an example of active transport. Why is this considered active transport and not passive transport? _________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Instructions Go to www.MrLeLivingEnvironment.weebly.com Click on “Living Environment Units” and scroll down to Unit 2->select Transport Watch the “Active Transport clip” to help you answer the question on the following slide.

Question: How is active transport different than passive transport Question: How is active transport different than passive transport? Your answer must have at least 2 differences. ______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

ATP is being used to move the molecules out of which cell(s)? cell A, only cell B, only both cell A and cell B neither cell A nor cell B