The Cell Membrane Why is the job of the cell membrane so important for the cell? Turn to your partner and talk about these reasons. Who would like to report out your thoughts. What does the membrane look like, draw it Homeostasis: an organisms ability to maintain an internal stable environment. How is cell membrane transport vital to an organisms homeostasis? Within your group draw what you remember to be the structure of the membrane 1. What will go in and out of the cell 2. Are there any regulators to enforce what goes in or out? 3. If homeostasis is maintaining a stable internal environment, what role does the cell membrane play? “Water loving” “Water disliking” THE CELL MEMBRANE Review terms Integral protein: embedded protein spanning from 1 end of bilayer to the other. Help ions and molecules travel into the cell. What’s the difference between the two? Locate these on your membrane and label them Review Peripheral protein: sit on outside of cell and are connected to integral proteins as well as cytoskeleton filaments and aid in support Locate them on your membrane and label them. Review Glycoprotein: protein and carbohydrate Protein is connected to cell membrane Carbohydrate: cell recognition and receptors functions: cellular recognition, immune responses and receptors for hormones and neurotransmitters Which is the protein? Find it on your membrane and label it Review Cholesterol: embedded within the fatty acid chains in phospholipids. Helps to maintain fluid condition and the C-H tails from sticking together. What else do we know about cholesterol? Review Cytoskeletal filaments: Attached to the cell membrane on the inside of the cell. They help aid with support to the cell. 1.Label them on your membrane. 2. Identify the inside and outside of the cell on you Membrane model. Let’s review all the parts! OUTSIDE CELL CARBOHYDRATE GLYCOPROTEINS Or glycolipids PHOSPHOLIPID BILAYER CHOLESTEROL Peripheral protein Integral PROTEIN Integral PROTEIN INSIDE CELL Channel protein FLUIDITY MODELS Before bubble lab https://www.youtube.com/watch?v=Rl5EmUQdkuI After bubble lab http://www.dnatube.com/video/68/Membranefluidity Rate of Diffusion Set up 3 beakers: hot water, cold water, other Add 50 ml of each liquid into the beaker Add 2 drops of food coloring approximately at the same time and start timer Look for the food coloring to completely diffuse throughout the beaker Record time substance