What are the Effects of Osmosis?

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Transcript What are the Effects of Osmosis?

What are the Effects of Osmosis?
If you place a cell in a solution (mixture of 2
substances) Three things can happen.
1. Isotonic solution –When the concentration
of water is the same inside and outside cell
2. Hypotonic solution- When there is a higher
concentration of water outside cell, so water
moves into cell
3. Hypertonic solution- when there is a higher
concentration of water inside cell, so water
moves out of cell
Isotonic Solution
– Balanced conditions
– No difference between
cell & environment
• example: blood
• water flows across
membrane equally,
in both directions
• volume of cell doesn’t
change
Hypotonic Solution
• Higher concentration of water outside
cell, so water moves into cell
• A cell in fresh water
• example: Paramecium
• problem: gains water,
swells & can burst
• solution: contractile vacuole
– pumps water out of cell
• “Hyp-o” – High in H20!
• Hipp-o, “O”
Hypertonic Solution
• Higher concentration of water inside
cell, so water moves out of cell
– a cell in salt water
– example: shellfish
– problem: lose water
• shrinking cell
– solution: take up water
• “Hy-per” – High in particles
• Pinocytosis- cell drinking-engulfing
small particles.
• Phagocytosis- Cell engulfing- ex
Lysosomes fuse with a bacteria for
digestion
• Cyclosis- Movement of the cytoplasm
Methods of Transport
• Passive transport- movement from High to low
concentration. No energy is used
•
– This is also called Simple diffusion
• Active transport- movement from low to high
– A. needs energy
– B. opposite of simple diffusion
Simple Diffusion-Passive Transport
• Move from HIGH to LOW concentration
– “passive transport”
– no energy needed
–Which way will molecules flow?
Active transport
• Cells may need
molecules to move
against
concentration
difference
– need to pump
“uphill”
• from LOW to HIGH
using ATP
– protein pump
– requires energy ATP
Transport summary