Warm-Up Get out your test survey and fill in your test scores as they are given to you. What do you know about the cell membrane? What is the cell membrane made up of? Get out a piece of lined paper. Write your name, date, period, and the heading: Unit 4 Section 1 Plasma Membrane Fluid Mosaic Model. Draw the table with the following columns: Topic l Notes l Picture

Topic: Plasma Membrane Outer boundary to cell, controls what enters and leaves. Selective permeability– some things can pass through the cell membrane, others can not -allows for HOMEOSTASIS (internal balance)

Topic: Fluid Mosaic Model Proteins embedded in the lipid bilayer can move around and “float” among the lipids So many different kinds of molecules make up the cell membrane as a “fluid mosaic” Mosaic- art that involves bits and pieces of different colors or materials

Topic: Phospholipid Hydrophilic- describes water-loving phosphate heads Hydrophobic- used to described the water- water-hating fatty acid chains

Classwork 1.Intro. to Cell Membrane 1.Questions 2.Coloring 2.Flashcards for the following words: plasma membrane, selectively permeable, fluid mosaic model, hydrophilic, hydrophobic, phospholipid 3.Homework Questions!

Warm-Up 1.Test survey in bin?! 2.Take out your homework questions #1-9 and your calendar! 3.Answer the following in your warm-up section with the date: What is a phospholipid? Be sure to write the two parts and use the word hydrophobic and hydrophilic. 3. Begin labeling the cell membrane you picked up on the way in.

Transport Protein A protein that helps transport molecules too large to diffuse.

Marker Protein Marker proteins are like a label for the cell. It allows other cells to identify it. All of your body’s cells have a marker on them so that the cells know they are all a part of your body.

Receptor Protein Just like it sounds, receives things like chemicals and signals from other cells

Cholesterol Helps firm the cell membrane, so it’s not too fluid. It also makes certain sections of the membrane less permeable to small molecules that dissolve in water.

Review Intro. to Cell Membrane Cell Membrane Animation QUIZ!

Concentration Gradient How concentrated molecules are. Naturally moves from High to low.

Passive Transport Movement of substances across the cell membrane without the use of chemical energy Substances are moved DOWN the concentration gradient (high to low) Types: diffusion, facilitated diffusion, osmosis

Circulatory System Gases and material travel from blood to all kinds of cells in the body Examples of Passive Transport

Diffusion- molecules move from high to low concentration Facilitated Diffusion- Molecules move from high to low concentration WITH a transport protein but WITHOUT energy Facilitated Diffusion

Examples of Passive Transport Diffusion Respiratory System Gas exchange between alveoli (air sacs in lungs) and capillaries (tiny blood vessels)

Digestive System Monomers (from food) are absorbed in the small intestines Examples of Passive Transport Facilitated Diffusion

Osmosis Diffusion (movement from high to low) of water through a selectively permeable membrane

Urinary System The kidneys filter out toxins from the blood Regulates water balance Examples of Passive Transport

Example of Osmosis Absorption of water by root hairs for plants

Active Transport Movement of molecules AGAINST/UP the concentration gradient (from low to high concentration) Requires ENERGY! Types: Endocytosis, Exocytosis, Ion Pump

Endocytosis Taking material into the cell using pockets of the cell membrane Endo- means “within”

Examples of Active Transport Immune System White Blood Cells destroy invading pathogens

Exocytosis A vacuole fuses with the cell membrane to release material Exo- means “outside”

Ion Pump Special transport proteins change shape to move molecules AGAINST/UP the concentration gradient across the membrane Requires energy

Examples of Active Transport Creating Concentration Gradients There is a lot of Potassium inside of the cell and a lot of Sodium outside of the cell to create a concentration gradient needed for sending electrical messages

Solutions Solute -what’s being dissolved (sugar, salt, etc.) Solvent -what’s doing the dissolving (water) Solution The combination of solute and solvent.

Hypertonic Solution Which way will the water go? Water goes out the cell. How does it move? Osmosis

Hypotonic Solution Which way will the water go? Water enters the cell. How does it move? Osmosis

Isotonic Solution Which way will the water go? Water enters and leaves the cell at the same rate. How does it move? Osmosis

Solutions