Bell ringer: How do things get in an out of a cell?

TRANSPORT IN CELLS

Observe the balloon on your table. Write down what you notice about these balloons. Remember, observations use ALL senses.

BALLOON OBSERVATIONS

How could you smell what was inside the balloon?

BALLOON OBSERVATIONS

The cell membrane is responsible for making sure certain things cannot get in, while others can

Some things are small and ALWAYS needing to go in and out. Just like the balloon, the cell membrane allows some things to come and go.

Can you think of things that are small and the cell needs constantly?

CELL MEMBRANE

Water

Oxygen

Carbon Dioxide

Waste

THINGS THAT A CELL NEEDS

Things that are small enough can go across the cell membrane without help or trouble. They don’t use any energy.

What makes them move then? In diffusion, molecules go from areas of HIGH concentration, to areas of LOW concentration.

Let’s try it.

DIFFUSION

Molecules move from areas of high concentrations to low concentrations.

A concentration gradient is a change of how much of something there is over a space

CONCENTRATION GRADIENT

Molecules move from areas where there are LOTS to LITTLE

They want to spread out!

DIFFUSION

http://www.brainpop.com/science/matterandchemistry/diffusion/

Why can you smell someone’s perfume from across the room?

DIFFUSION

Earlier today I placed a normal piece of potato in two different liquids: water and salt water.

Potatoes have a lot of water in their cells.

What do you think will happen to the water in the potato cells in each of these liquids?

DIFFUSION

With your neighbor, discuss why the potatoes looked different.

THINK-PAIR-SHARE

http://www.brainpop.com//science/matterandchemistry/diffusion/quiz/

REVIEW

Bell Ringer: Think of a real-life situation where diffusion occurs.

PASSIVE TRANSPORT

http://www.youtube.com/watch?v=0c8acUE9Itw&feature=related

Osmosis is the diffusion of water

OSMOSIS

What happens when something is too big to get through the membrane?

FACILITATED DIFFUSION

The molecule might need a little help getting through the membrane.

Certain proteins can help the molecule get into the cell and still go along the concentration gradient.

Since no energy is used, this is diffusion. But since the molecule needs help (or facilitation) it is called facilitated diffusion.

FACILITATED DIFFUSION

http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_facilitated_diffusion_works.html

FACILITATED DIFFUSION

Whenever a cell uses NO ENERGY to move something it is called passive transport.

Thus far, we know 3 kinds of passive transport: diffusion, facilitated diffusion and osmosis

http://www.brainpop.com/science/cellularlifeandgenetics/passivetransport/

PASSIVE TRANSPORT

Osmosis

DiffusionFacilitated Diffusion

Bell ringer: What are the three kinds of passive transport we have already learned? What do they have in common?

ACTIVE TRANSPORT

Whenever a cell uses NO ENERGY to move something it is called passive transport.

Thus far, we know 3 kinds of passive transport: diffusion, facilitated diffusion and osmosis

REVIEW

http://www.youtube.com/watch?v=yZ15vCGuvH0

Our muscles use something called ACTIVE TRANSPORT!

MUSCLES!

Sometimes, a cell wants to move something from a low concentration to a high concentration.

ACTIVE TRANSPORT

Some examples of this include: moving ions in muscles, moving sugar into a cell, moving hormones into or out of a cell

Whenever a cell moves something against the concentration gradient it must use energy

Active transport is transport that uses energy

ACTIVE TRANSPORT

Energy in a cell is known as ATP

ACTIVE TRANSPORT

http://www.brainpop.com/science/cellularlifeandgenetics/activetransport/preview.weml

ACTIVE TRANSPORT

ACTIVE VS. PASSIVE

Active Passive

Explain how things move into and out of the cell with active transport. Use the following words in your explanation: energy (or ATP), concentration gradient, substance, cell membrane.

QUICK WRITE

Moving things into cell ALWAYS requires energy.

The cell membrane can control what goes in and out.

Diffusion uses no energy.

In active transport, things are pushed from an area of high concentration to low concentration.

AGREE OR DISAGREE

Questions 1-6 on the worksheet due tomorrow!

HOMEWORK