Egg lab day 1

Demonstration & Vocabulary In journal, make a title: ‘Diffusion Demonstration’ & draw the two flasks as shown below. START FINISH

Vocabulary (in your Egg Lab Booklet, page 7) Solution: a mixture of two or more substances that are evenly distributed. Solute: the substance that gets dissolved in a liquid solution. Solvent: the substance that does the dissolving in a liquid solution.

Example In the ocean, the water is the solvent and the salt is the solute.

What is the solute and solvent in each example solution (write in journal): Kool-Aid Solvent: Solute(s): Hot Chocolate Solvent: Solute(s):

What is the solute and solvent in each example solution (write in journal): Kool-Aid Solvent: water Solute(s): flavor, sugar Hot Chocolate Solvent: milk (or water) Solute(s): chocolate flavor powder, sugar

Demonstration- part II Now draw the finish diagram and describe in words what happened from beginning to end START FINISH

More Vocabulary Diffusion: the movement of substances from high concentrations to low concentrations until an equilibrium is reached. (CO 2, O 2 ) Osmosis: the diffusion of water (from high concentrations to lower concentrations) through a selectively permeable membrane (until an equilibrium is reached).

Egg lab day 2 Yeah…the shell is gone! Now we can get at the cell membrane.

Beaker A: 200 mL water 20 mL food color Beaker B: 200 mL water 40 mL food color Make a title in your journal “Comparing Concentrations” and copy down the pictures and labels below.

Beaker A: 200 mL water 20 mL food color Beaker B: 200 mL water 40 mL food color Please answer the following questions in complete sentences. 1.Which beaker has more water? 2.Which beaker has more food color? 3.Which beaker has a greater concentration of food color? 4.Which beaker has a greater concentration of water?

More practice: please copy down the example below in your journal. Quick sketches are fine! Be sure to label with amounts of tea and sugar for each. Cup A: 12 oz of tea 1 oz sugar Cup B: 8 oz of tea 1 oz sugar

Finish Each: 1. Cup _____ has more tea. 2. Cup _____ has more sugar. 3. Cup _____ has a greater concentration of sugar (solutes). 4. Cup _____ has a greater concentration of tea. Cup A: 12 oz of tea 1 oz sugar Cup B: 8 oz of tea 1 oz sugar

Name: ______________ Formative Quiz: Pitcher A: 1 liter water 100 mL lemon juice 1.Which pitcher has more water? 2.Which pitcher has more lemon juice? 3.Which pitcher has a higher concentration of lemon juice? 4.Which pitcher has a high concentration of water? Pitcher B: 1 liter water 200 mL lemon juice

Vocabulary Review Diffusion: the movement of substances from high concentrations to low concentrations until an equilibrium is reached. (CO 2, O 2 ) Osmosis: the diffusion of water (from high concentrations to lower concentrations) through a selectively permeable membrane (until an equilibrium is reached).

The red blood cells are very important to survival because they transport oxygen from lungs to the cells of the various tissues (muscles, nerves, etc.). These blood cells are transported in a fluid (serum) that has approximately the same salt content as sea water. If someone were admitted to the hospital and was in need of an IV (intravenous fluids) why is it critical that the concentrations of solutes (i.e. salts) in the IV is similar to that in the blood stream? 1.What would happen to the blood cells if the IV were too salty? 2.What would happen to the blood cells if the IV was pure water (less salty than water)? OSMOSIS AND BLOOD CELLS

Blood Cells in different solutions Dehydrated Cells: water leaves cells because the solution that cells are in is too salty. Bloated Cells: water enters cells because the solution that cells are in is not salty enough. Happy Cells: concentration of salts equal in and out of cells.

Why do sports drinks contain ‘electrolytes’ (salts) in addition to water and sugar?

Egg lab day 3

Conclusions For your Egg Lab, explain WHY the egg in pure water got bigger. Hint: remember only water can pass through the egg’s membrane.

The egg in pure water got bigger because: Since water is the only substance that can go the through the egg membrane, water entered the egg (the egg absorbed water) But WHY did water enter the egg?

Water always moves from HIGH CONCENTRATIONS to LOW CONCENTRATIONS during osmosis. Since the concentration of water was highest outside the egg (pure water = 100 % water), water then enters the egg.

What happened to the egg placed in corn syrup?

Why did the egg in corn syrup get smaller(less mass)? Why did water leave the egg?

Corn syrup is about 25% water, the egg is about 90% water. Water always move from high concentration to low concentration…so water diffused through the egg membrane and entered the corn syrup solution – OSMOSIS!

Finish conclusions – pages 5+6

after the Egg Lab

Definitions Passive Transport: Transportation of materials in and out of cells using diffusion or osmosis; does not require the cell to use energy. Facilitated Diffusion: the diffusion of larger molecules through special channel proteins in the cell membrane.

Endocytosis Model: How do cells get really BIG molecules in or out of the cells? Materials Plastic Bag (cell membrane) candy (large ‘food’ molecules) String Scissors Problem: The bag at your table represents a cell membrane. The cell really wants the food molecules (candy), but they are too big to pass through the membrane.

Endocytosis Model: How do cells get really BIG molecules in or out of the cells? Your job is to figure out a way for the cell to get the food molecules (candy), without ever exposing the inside of the cell to the outside world or without ever having an OPEN HOLE in the bag. Remember that the cell is filled with cytoplasm (liquid). When getting the food molecules there should never be an opportunity for any cytoplasm liquid to escape. Good luck! The first group to successfully solve this problem gets an additional food molecule (candy)!

Cell absorbs a large amount of material such as a glucose molecule.

Cell releases a large amount of material such as waste or protein.

Definitions Active Transport: When energy is required to transport materials in or out of cells. When a cell uses energy to obtain or get rid of something it needs. For example, it would take energy to move materials against diffusion.

Definitions Examples of Active Transport: Molecular Transport (Pumps): Protein molecules in the cell membrane act like pumps and work against the forces of diffusion. Examples: calcium, potassium, or sodium. Endocytosis/Exocytosis: Large molecules can be transported when the cell ‘engulfs’ them (endocytosis). In reverse it is exocytosis.

Group Task: Complete the chart using your notes. Type of Movement Energy Required? Passive or Active Transport? What type of particle is moved? What part of the membrane is the particle moving through? How does it work? Explain (show picture) Diffusion Osmosis Facilitated Diffusion Molecular Transport Endocytosis Exocytosis

Type of Movement Energy Required? Passive or Active Transport? What type of particle is moved? What part of the membrane is the particle moving through? How does it work? Explain Diffusion No energy needed. Passive Transport O2 CO2 Lipid bi-layerParticles diffuse through the membrane until the concentrations in/out of the cell are balanced (equilibrium). Osmosis No energy needed. Passive Transport H20Lipid bi-layerWater moves through the membrane until concentrations in/out of the cell are at equilibrium. Facilitated Diffusion No energy needed. Passive transport Glucose, sodium, potassium, calcium Protein channel Particles move from high to low concentrations through the protein channel. Molecular Transport Energy needed. Active transport Sodium, calcium, potassium Protein pumpThe cell uses energy to pump the particles against the concentration (from low to high!). Endocytosis Energy needed. Active transport Large molecules or clumps of material such as glucose. The whole membrane. The particle(s) are too big to fit through the proteins or lipids so the cell membrane folds over the particles and then pinches off. Exocytosis Energy needed. Active transport Large molecules, clumps of material such as waste or proteins. The whole membrane The membrane folds and pinches together to allow the particles to escape.

Cell size

Warm-up Please write down the dimensions of the two theaters below Theater A: capacity 200 people and 6 exits Theater B: capacity 800 people 16 exits Scenario: you go to the theater or to the movies. You take the prime center seats to view the movie. It is a full house (all seats filled).

Warm-up Theater A: capacity 200 people and 6 exits Theater B: capacity 800 people 16 exits Unfortunately, there is a fire and the theater needs to be evacuated. Which theater would you rather be in, if you were to find yourself in this unfortunate incident? Discuss as group and be prepared to report out. Explain you answer in your journal.

Summarize why ‘large surface area to volume ratios’ are an advantage for cells:

Surface-area represents ______________ of cell, while volume represent contents of a cell. The membrane allow material to enter and exit (provide passage ways). Therefore, it is an advantage to have lots of ____________ in relation to the cell volume (or a large SA/V ratio) so that material can exit and enter _________, consequently ____________ cells are quicker at getting things in and out. Just like small theater analogy.