Download Osmosis and Diffusion

Name: _______________________________________ Period: ______ Date: _____________________ Osmosis and Diffusion Cell membranes separate the _______________ of the cell from the outside environment. They control what _______________ and _______________ the cell—maintaining homeostasis. Molecules can move across the membrane via ___________________ transport (with energy), or ________________ transport (without energy). Small molecules like water (H20), and carbon dioxide (CO2), and oxygen (O2) travel across the membrane easily via passive transport. Molecules ALWAYS move from ___________ concentration to ____________ concentration, until the system is at ______________________________. Two examples of passive transport: ______________________ and ______________________ Diffusion: _____________________________________________ _______________________________________________ •
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Molecules spread from an area of __________ concentration to an area of __________ concentration until equilibrium. EXAMPLES: Draw/Describe what happened in the demonstration. 1. Food Coloring in Water 2. Air Freshener _________________________________________________________________
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_________________________________________________________________ Name: _______________________________________ Period: ______ Date: _____________________ Osmosis: _____________________________________________ •
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______________________________________________ Move from a higher concentration of ___________ (lower concentration of solute) to a lower concentration of _________. Remember: “SALT SUCKS” o Salt is a solute. When it is concentrated inside or outside the cell, it will draw water ______________ itself. o Why do you get thirsty after eating something salty? ________________________________________________________________________
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Water comes into plant cells through osmosis creating ______________ _______________ to hold the plants upright, creating pressure against the cell wall. Comparing Diffusion and Osmosis: Use the Venn Diagram below to compare these two types of passive transport. DIFFUSION OSMOSIS HSA Practice Questions: 1.
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Which of these substances moves across cell membranes by osmosis?
A. Salt
B. Sugar
C. Water
D. Protein
Many bacteria live in fresh water. Which of these statements best describes what will happen
when freshwater bacterial cells are placed in salt water?
A. Water leaves the cell, causing the cell to expand.
B. Water leaves the cell, causing the cell to shrink.
C. Water enters the cell, causing the cell to expand.
D. Water enters the cell, causing the cell to shrink.