Egg LabPage 33 Essential Question: Question ColumnEgg in VinegarEgg in SyrupEgg in Water L1 – L2 – L3 – Prediction: Hypothesis: Observation: Diagram: Prediction: Hypothesis: Observation: Diagram: Prediction: Hypothesis: Observation: Diagram: Summary - Bellwork: On bellwork write “Set-Up Egg Lab Notes and Study for Cell Quiz” Get goggles and aprons. Put backpacks all the way under your table. Notecard definitions due on Friday. Set up “Cornell Notes” Handout (the one you just picked up on the front table) exactly as you see in the diagram to the right. Add color. Rulers are in the Aggie Cabinet. How do molecules move across the cell membrane?

Cell Quiz! When done with the quiz, draw the following data table on the back of PG 33(Cornell Notes - Egg Lab): Original MassFinal MassDifference in Mass VINEGAR XXXXXXXXX SYRUP WATER

Standard B.4B – Investigate and explain cellular processes, including homeostasis, energy conversions, transport of molecules, and synthesis of new molecules Essential Question How do molecules move across the cell membrane? PG 34

Egg LabPage 33 Essential Question: Question ColumnEgg in VinegarEgg in SyrupEgg in Water L1 – L2 – L3 – Prediction: Hypothesis: Observation: Diagram: Prediction: Hypothesis: Observation: Diagram: Prediction: Hypothesis: Observation: Diagram: Summary - How do molecules move across the cell membrane? TODAY – NOW TODAY – Wait for it….. TOMORROW

The shell that surrounded your egg was dissolved by soaking the egg in vinegar for 24 hours. The vinegar dissolved the hard calcium carbonate shell exposing the semi-permeable membrane that surrounds the egg. This membrane is very similar to the plasma membrane that surrounds all of our cells. The purpose of this lab is to simulate osmosis across a plasma membrane. Students will receive one egg per lab table.

Day 1 Procedure… 1.Using your hands, carefully remove your egg from the vinegar and use the water bath to CAREFULLY remove the shell. Use a paper towel to pat it dry. 2.On your Cornell notes, record your observations (firmness and overall appearance) of your egg in the VINEGAR row. Draw a diagram. 3.Mass (weigh) your egg on a scale and record your results on your data table. Enter the weight under the “Final Mass” for VINEGAR and the “Original Mass” for SYRUP. 4.Using a marker, label the beaker with your period # and table letter. Cover the egg with syrup until it begins to float. 5.Allow your egg to sit for 24 hours.

Egg LabPage 33 Essential Question: Question ColumnEgg in VinegarEgg in SyrupEgg in Water L1 – L2 – L3 – Prediction: Hypothesis: Observation: Diagram: Prediction: Hypothesis: Observation: Diagram: Prediction: Hypothesis: Observation: Diagram: Summary - How do molecules move across the cell membrane? TODAY – DONETODAY – NOW TOMORROW

Diffusion Notes Why does food coloring spread out in water?

Every living thing lives in a liquid environment that it needs to survive.

One of the most important functions of the cell membrane is to regulate the movement of dissolved molecules from the liquid on one side of the membrane to the liquid on the other side.

The concentration is the amount of a substance dissolved into water.

Kool-Aid Beaker 1 Beaker 3 Beaker 2

In a solution, particles are constantly moving. They collide with one another and tend to spread out randomly.

Particles move from an area of high concentration to an area of low concentration. This process is known as diffusion.

A concentration gradient is a difference between two concentrations. Diffusion is the movement of particles down the concentration gradient.

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.

Substances that diffuse across a membrane do not require the cell to use energy.

If a substance is able to diffuse across a membrane, the membrane is said to be permeable to it. If a substance cannot diffuse across a membrane, the membrane is said to be impermeable to it.

Selectively permeable means that some substances can pass across while others cannot. Biological membranes are selectively permeable.

Start foldable if time…….