Cell Membrane Review Name: ________________________________ Period: ______ Date: ______________ Composition of the Cell Membrane: The cell membrane is also called the ____________ _______________________. The phospholipids in the cell membrane form two layers called a _________ _____________. The 3 main components of the cell membrane are _________________, _________________ and ______________________. LABEL THE CELL MEMBRANE The phospholipid molecule has a hydrophilic (water attracting) ________ _______ and two hydrophobic (water repelling) __________ _______. LABEL THE PHOSPHOLIPID Explain the Fluid Mosaic Model: ____________________ ______________________________________________ List the 4 Functions of the Cell Membrane: 1. 2. 3. 4. Explain what Semi Permeable means:

3 types Transport Across the Membrane The two main types of membrane transport are ____________________________ and _______________________________. Passive Transport Active Transport No ___________ required Needs _____________ ________ to ________ concentration Going __________ the concentration gradient 3 types 1. 2. 3. Explain what happens during each type of passive transport. Diffusion: Osmosis: Facilitated Diffusion: Define Equilibrium – Define Osmosis -

Osmosis – Write the correct type of solution underneath the diagram (ISOTONIC, HYPERTONIC, HYPOTONIC) A. ________________ B. ________________ C. _________________ ________________________ - there is a GREATER concentration of solute molecules outside the cell than inside. ________________________ - there is a LOWER concentration of solute molecules outside the cell than inside. ________________________ - there is the SAME concentration of solute molecules outside the cell as inside. LABEL THE TONICITY FOR EACH SOLUTION (HYPERTONIC, ISOTONIC, HYPOTONIC) Pay close attention to the direction that water is moving. 1. _______________ 2. ______________ 3. _______________

Matching – Match each term to its definition Energy ____1. particle movement from an area of higher concentration to an area of lower concentration Facilitated diffusion ____2. a form of passive transport that uses transport proteins Endocytosis ____3. is used during active transport but not passive transport Passive transport ____4. process by which a cell expels wastes from a vesicle Active transport ____5. particle movement from an area of lower concentration to an area of higher concentration. Exocytosis ____6. process by which a cell takes in material by forming a vesicle Osmosis ____7. the concentration of solute is equal between the outside and inside of the cell. Isotonic ____8. movement of water across a membrane. Tonicity: Place an X in the correct box STATEMENT Isotonic Hypertonic Hypotonic 1. The concentration of the solute in the solution is lower than the concentration inside the cell. 2. When a cell is placed in this solution, water will enter the cell. 3. Type of solution that animal cell prefer. 4. The preferred solution that gives plant cells good turgor pressure. 5. When this solution is injected into the body, no cell disruption occurs because no net osmosis occurs. 6. The concentration of the solute in the solution is higher than the concentration inside the cell. 7. The concentration of the solute in the solution is the same as inside the cell. 8. Plant cells go limp when put in this solution. 9. When a cell is placed in this solution, water will leave the cell. Describe what happened to the shell-less eggs in hypotonic and hypertonic solutions.

Explain the difference between diffusion and facilitated diffusion: ______________________ __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ The three types of active transport are _________________________, ________________ and __________________________. Identify and label the 3 types of active transport: 1. ______________________ 2. ____________________ 3.______________________ Name and describe the 2 types of endocytosis: 1. 2. Can water kill you? The New York Times article by John O’Neil Runners who get dehydrated face obvious dangers, but drinking too much water during a race can also be deadly. Doctors investigated seven cases in which runners who collapsed after a marathon were found to have a shortage of salt in the blood. One of the runners died. Fears of dehydration have led to a mistaken belief that the safe thing to do in a marathon “is to drink as much as you can, as often as you can”. During a race, so much blood is diverted to the muscles that the intestines are unable to absorb the water a runner drinks. Once the race ends, the water floods into the blood stream and disrupts the body’s salt balance. This can cause the brain to swell, which in turn sets off a mechanism that releases water into the lungs. The treatment for the condition is simple: add more salt to the bloodstream. But the fluid in the lungs and the circumstances of the collapse lead to emergency room doctors to suspect heart trouble and to order treatments that make things worse. Explain in terms of tonicity what is occurring in the body. ____________________________ __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________ __________________________________________________________________________