First Five Silently in your notebooks, draw a low powered and high powered image using your drawing guidelines.

Announcements Due Today Make sure you are turning in all past homework Magnification Cell Drawing Homework Make sure you are turning in all past homework

Finishing Lab Remaining Groups should do Microscope Lab Everyone else work on Interactive Notebook, Missing work and Homework due Today

First Five Which cell structure controls movements in and out of cells? Distinguish the difference between cell membrane and cell wall? What do you think the term osmosis means? The term diffusion?

Some additional notes Tissue: a group of cells with similar structures, working together to perform a shared function Organ: a structure made up of a group of tissues, working together to perform specific functions Organ system: a group of organs with related functions, working together to perform body functions

Passing the membrane… Movement in and out of cells

Think and Share Take a few minutes and write in your notebook what you think the difference is between osmosis and diffusion.

Food Dye Experiment Predict what would occur when food dye is dropped into a beaker filled with water. Do you think this would be osmosis or diffusion

Molecules move from area of HIGH to LOW concentration DIFFUSION Requires NO energy Molecules move from area of HIGH to LOW concentration Molecules move down their concentration gradient

What about food dye? DIFFUSION What happens to food dye that you drop into one spot in a cup of water? DIFFUSION MOLECULES OF FOOD COLORING ARE MOVING FROM HIGH CONCENTRATION TO LOW CONCENTRATION TO SPREAD OUT EVENLY IN THE WATER

Diffusion Driven by (powered by) the concentration gradient NO energy used Energy for diffusion comes from the kinetic energy of random movement of molecules and ions Concentration gradient: the difference in the concentration of a substance from one location to another

A lot of Very little Particles particles High concentration low concentration

OSMOSIS: specific type of diffusion The diffusion of water molecules across a partially permeable membrane Moves from an area of high concentration of water to areas of low concentration of water What is another way to say “high concentration of water”?

Osmosis: more terms Water diffuses down its gradient Higher concentration of WATER= Dilute solution= High water potential Lower concentration of WATER= Concentrated solution= Low water potential Water diffuses down its gradient moves from a region of high water potential to a region of low water potential

WATER CHASES MOLECULES! WATER WANTS TO DILUTE SOLUTIONS SO IT WILL ALWAYS MOVE FROM A PLACE WHERE THERE ARE LESS MOLECULES TO A PLACE WHERE THERE ARE MORE MOLECULES!

CFU: Which way will the molecules move by diffusion?

CFU: Does moving the molecules in this direction require energy?

CFU: If these were salt molecules moving, would this be diffusion or osmosis?

CFU: If these were water molecules moving, would this be diffusion or osmosis?

Osmosis in Cells Recall that cytoplasm is a solution of protein and substances in water Cells are usually also surrounded by fluids When the solutions are different concentrations osmosis occurs

Animals Cells Hypertonic: water leaves the cell to enter the more concentrated solution Isotonic: Water enters and leaves at the same rate Hypotonic: water enters the cells since the cytoplasm is more concentrated

Plant Cells As osmosis occurs in plants cell, both the cytoplasm and the vacuole will lose or gain water.

What was the specialized cell of a plant that absorbed water and minerals?

Exit Ticket Explain how diffusion works (use high and low gradient concentrations) Explain how osmosis works State the differences between diffusion and osmosis Osmosis Rap

Animal Uptake

Active Transport