Movement Through Membranes

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Movement Through Membranes

• SPI.1.7 Predict the movement of water and other
  molecules across selectively permeable membranes.
• SPI.1.8 Compare and contrast active and passive
  transport.

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Cell Membrane
Phospholipids Create barrier
Carbohydrate Chains Communication
Selectively Permeable Picky about what gets
through
Proteins Allow molecules to pass through
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Solution homogenous mixture
Solute Dissolved particles
Solvent Dissolving liquid
Solution
Mixture solute solvent
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Concentrations
Mass Amount Solute (grams)
Volume Amount Solvent (Liters)
Concentration Mass per Volume (g/L)


Which liquid has a higher concentration?
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Two Types of Transport

• Passive
• Types of Passive
• Diffusion
• Osmosis
• Facilitated Diffusion

• Active
• Types of Active
• Ion Pumps
• Endocytosis
• Exocytosis

Difference? No Energy Energy Needed
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Diffusion
Movement of particles (solutes)
High Concentration
Low Concentration
Goal?
Equilibrium
Energy
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Diffusion Demo
Base
Phenolphthalein

Phenolphthalein
Base

Pink
Color?
Color?
White-Clear
Clear
Results The bag was__________________ The
beaker was _______________ The plastic bag was
semi permeable to _________________
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Osmosis
The movement of water across a membrane
Low solute
High solute
High water
Low water
Water goes to the higher concentration (bigger
number of solutes)
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Tonicity
Concentration difference between two solutions
separated by a semi permeable membrane
Hypotonic
Hypertonic
Isotonic
Low conc. of solutes
High conc. of solutes
Equal conc. of solutes
Water moves into the cell
Water moves in out the cell
Water moves out of the cell
Cells will swell
Cells will shrink
Cells will stay the same
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Osmosis in Blood Cells
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Hypotonic
Hypertonic
Isotonic
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Move from areas of High to Low Concentrations
Movement through protein channels
NO Energy Required!
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Need energy!
Movement from areas of low to high concentration
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Ion Pumps
Movement from areas of low to high concentration
Movement through protein channels
Need Energy!
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Endocytosis
Membrane surrounds and brings in large particles
Need Energy!
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Exocytosis
Packaged materials from Golgi are pushed through
the membrane to the outside of the cell
Need Energy!
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