 Learning Goal: Demonstrate Osmosis & Diffusion through lab simulations. Warm up: What element do all organic compounds contain? Homework: Virtual Lab #1-7 (use complete sentences) Study for TEST ON FRIDAY – Ch. 3 Sec. 1 & 2 Monday 10/19/15

 Station 1: EGGSPERIMENT WITH a CELL- 10 min *READ THROUGH FIRST* One of the cell structures you are learning about is the cell membrane. In the Project, you will model how a cell membrane works to let water enter and leave the cell. You will use a chicken egg as a model of a cell. After dissolving the shell in vinegar to expose the membrane, you will soak the egg in various liquids and observe how the size and mass of the egg changes as it takes on or loses water through the membrane. You also will keep a record of observations and measurements of the egg. PROCEEDURE (record data on packet page 12) Day 1: As soon as you get your egg, observe its features and measure its circumference. Record your observations and measurements (should be detailed and precise). Place your egg cell in a cup. Place your group names on the cup. Pour vinegar over the egg until it is covered. This will dissolve the hard shell, leaving only the membrane. Soak the egg in vinegar for at least two days. Then observe and record how the egg has changed, including any changes in appearance or texture. Also measure the circumference of the egg, using the procedure described on the bottom of the page. Record your observations and measurements. Day 2: Soak the egg in colored water for one or two days. Observe and record how the egg has changed and measure and record its circumference. Day 3: Soak the egg in salt water. Continue to keep careful records of observations and measurements of the egg’s circumference and other qualities. Day 4: Soak the egg in corn syrup. Continue to keep careful records of observations and measurements of the egg’s circumference and other qualities. Graph the data you have collected and prepare a report of your results. Be prepared to explain your results and show your egg to the class. HINTS For the best results in this project, it is important to measure your egg carefully each day. This is because changes in circumference of the egg may be slight, and measurements that are not precise may mask changes that have occurred. Follow these steps when measuring the egg each day. 1. Carefully take the egg out of the liquid and pour the liquid down the drain (or in our class the bucket). 2. Rinse off the egg in cold water and blot it dry with a paper towel. 3. Using a measuring tape, measure the circumference of the egg in cm to the nearest.0. Wrap the tape snugly around the middle of the egg at the equator but be careful not to cut into the egg’s membrane with the tape. 4. Record your measurements and any other observations about the egg in the data table. 5. Return your egg to the container and cover it with another liquid, according to the project rules above.

 For the best results in this project, it is important to measure your egg carefully each day. This is because changes in circumference of the egg may be slight, and measurements that are not precise may mask changes that have occurred. Follow these steps when measuring the egg each day. 1.Carefully take the egg out of the liquid and pour the liquid down the drain 2.Rinse off the egg in cold water and blot it dry with a paper towel. 3.Using a measuring tape, measure the circumference of the egg in cm to the nearest.0. Wrap the tape snugly around the middle of the egg at the equator but be careful not to cut into the egg’s membrane with the tape. 4.Record your measurements and any other observations about the egg in the data table. 5.Return your egg to the container and cover it with another liquid, according to the project rules above. Follow these steps when measuring the egg each day.

 Station 1: EGGSPERIMENT Hypothesis: DateLiquidHypothesis Friday 10/16/15 Vinegar If I place an egg in vinegar, then … Monday 10/19/15 Colored Water If I place an egg in colored water, then … Tuesday 10/20/15 Salt Water If I place an egg in salt water, then … Wednesday 10/21/15 Corn Syrup If I place an egg in corn syrup, then …

 Station 1: EGGSPERIMENT Data table: DateLiquidCircumference (in millimeters) Other observations Friday 10/16 None Monday 10/19 Vinegar Tuesday 10/20 Colored Water Wednesday 10/21 Salt Water Thursday 10/22 Corn Syrup