H APPY M ONDAY !! Bellwork: Draw a representation of the picture below. Use your drawing to explain why it is important for cells to be small.

A CTIVITY : Open your journals Set up page number ____ for Cornell Notes Your first entry on the left hand side should be “Observations”. You should all have a set of random objects at your tables. For the next 7 minutes you will explore and record as many observations as you can about the items at your table. (CHAMP) Write down ANYTHING you observe. There are no right or wrong answers.

T ODAY ’ S E SSENTIAL Q UESTION What is a membrane and what is it’s purpose? What did you observe in the activity and how does it relate to the essential question?

A LL CELLS ARE SURROUNDED BY A THIN, FLEXIBLE BARRIER KNOWN AS A CELL MEMBRANE.

W HAT IS THE CELL MEMBRANE ’ S FUNCTION ( JOB )? (2 THINGS )

T HE TWO MAIN FUNCTIONS ARE : 1) TO REGULATE WHAT ENTERS AND LEAVES THE CELL 2) TO PROVIDE PROTECTION AND SUPPORT.

M EMBRANES FALL INTO THREE CATEGORIES … They can be permeable, meaning that the membrane is penetrable and will allow liquids, particles and gasses to pass through it. Which of the objects from the activity were completely permeable?

They can be impermeable, meaning that the membrane is not penetrable and will NOT allow liquids, particles or gasses to pass through it. Which of the objects from the activity were completely impermeable?

Finally, they can be Selectively permeable, meaning that some substances can pass across while others cannot. Biological membranes, like the ones around your cells, are selectively permeable. Which of the objects from the activity were selectively permeable?

W HAT IS THE CELL MEMBRANE MADE ( COMPOSED ) OF ? (3 TYPES OF MOLECULES )

The cell membrane is composed of a double-layered sheet called a lipid bilayer. DRAW THIS! Lipi d Phosphate carbohydra te Bi- means 2 Also called the phospholipid bilayer

P ROTEINS ARE EMBEDDED IN THE LIPID BILAYER. Proteins form channels or pumps that help move large materials across the cell membrane.

Carbohydrates are attached to many proteins embedded on the outside of the bilayer. The carbohydrates allow individual cells to identify one another.

H APPY T ERRIFIC T UESDAY TO YA !!! Bellwork: Draw the picture below and label the essential parts we discussed yesterday.

Q UICK R ECAP ! Why do molecules move? How do molecules move? 1. Concentration gradient What is it? How does it affect how molecules move? 2. Types of solutions: Isotonic Hypertonic Hypotonic

E SSENTIAL Q UESTION : W HAT IS THE PROCESS OF DIFFUSION ? W HAT IS THE PROCESS OF OSMOSIS ? A ND HOW DOES IN THE WORLD DOES IT RELATE TO WHAT WE ’ VE BEEN TALKING ABOUT ?

Diffusion: when particles move from an area of high concentration to an area of low concentration.

Osmosis : diffusion of WATER through a selectively permeable membrane Remember: SALT SUCKS

When the concentration of a solute is the same throughout a system, the system has reached equilibrium. When equilibrium is reached, particles do continue to move across the membrane.

M OLECULE T RANSPORT V OCAB DID HOMEWORK Concentration gradient Hypotonic Hypertonic Isotonic Diffusion Osmosis Equilibrium Create a concrete spelling for 3 of the words (color) DIDN’T DO HOMWORK Pg 201 (diffusion), (hypo/hyper/iso) Questions #2 and 3 on page 207

B ELLWORK You’ll have 5 minutes to finish your concrete spelling OR bookwork from yesterday Pg 201 (diffusion), (hypo/hyper/iso) Questions #2 and 3 on page 207

S CIENCE F ACT OF THE D AY Salt water is 4 times saltier than our blood. By drinking it, your kidneys would need to use up a large amount of water just to get rid of all that excess salt. This means that you would actually die of thirst from drinking seawater.

Osmosis with Gummi Bears Purpose To investigate the movement of water into and out of a semi- permeable membrane Hypothesis: If the Gummi Bear is placed into an isotonic solution, then it will ____________ in mass. If the Gummi Bear is placed into a hypertonic solution, then it will ____________ in mass. If the Gummi Bear is placed into a hypotonic solution, then it will ____________ in mass. Materials (1) Gummi Bear, (1) plastic cups, Paper towels Triple beam balance Permanent marker

Procedure 1.Obtain 1 plastic cup and 1 bear. 2.On the side of the cup, write your group name using a permanent marker. 3.Find the mass of each bear using a balance. Record the data in the data table. 4.Measure your bear from top to bottom (height), from side to side (width) and from front to back (length). Use your measurements to calculate the volume. Record your data in the data table. 5.Place the bears in the cups. 6.Pour either solutions A or B into the cup. Pour enough solution in the cups to fully cover the bears (1/2 cup full). 7.Place the cup on your tray and let them soak overnight. 8.On the next lab day, gently remove the bears from the solution. 9.Gently blot the bears dry by placing them on a paper towel. 10.Measure the bear. 11.Find the mass of the bear. Do this by placing the bear on the balance. Record the total mass. Carefully slide the bear back into the empty cup.

D ATA TABLE Bear in solution __ Length (cm) Width (cm) Height (cm) Volume (cm 3 ) Mass (g) Day 11 cm 2 cm2 cm g Day 2 Change

C ONCLUSION ( ON YOUR TABLE ) Each blank is numbered, fill in the word for the number DON’T copy the whole thing Analysis What type of solution was your bear in? (Justify your answer) Explain how a cell maintains homeostasis using osmosis.

S OLUTION TYPES WITH CHIPS … Homework Facilitated Diffusion Alyssa Dolny