Osmosis and Cytosis

• What is osmosis?

• What is the difference between a solute and a solvent?

• How do label areas of low solute concentration vs high solute concentration?

• What is the difference between endocytosis and exocytosis?

​Cues

​Main Idea: What molecules are brought into and out of the cell during diffusion, facilitated diffusion, osmosis, and active transport?

Osmosis is the passive diffusion of water (H₂O) molecules into and out of the cell membrane.

This moves with the concentration gradient (from high to low.

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concentration gradient - Molecules want to move from areas tightly packed with molecules to areas that are less crowded

What is osmosis?

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​An isotonic solution is one in which the solutes in the fluid are equal to that inside the cell.

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When the ​concentration is the same inside the cell, and outside the cell, it is considered to be in equilibrium. Flow will be equal inside and outside.

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​Some text here about the topic of discussion.

Water movement based on solute concentration​

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When the concentration of solutes inside the cell is greater than the surroundings.

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The net movement of water will be into the cell.​

Hypotonic​

When the concentration of solutes inside the cell is less than the surrounding fluids.

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The net movement of water will be out of the cell.​

​​Hypertonic

When the cell membrane pinches off and brings materials INTO the cell.

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This is needed for large molecules like protein chains or when white blood cells eat bacteria​.

Endocytosis

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When vesicles are brought to the membrane and materials are removed from the cell.

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This is how the cell removes waste products or brings lipids to the membrane​

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Exocytosis

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