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Cell Membrane Transport Notes. July 15, 2014. I.) Types of Cell Membrane Transport. There are 2 types of cell membrane transport: Passive Transport Does not require energy Things flow from High to low Active Transport Requires energy Ex- - Things flow from low to high
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Cell Membrane Transport Notes July 15, 2014
I.) Types of Cell Membrane Transport • There are 2 types of cell membrane transport: • Passive Transport • Does not require energy • Things flow from High to low • Active Transport • Requires energy Ex- - Things flow from low to high - moving a large/polar molecule
II.) Passive Transport • Diffusion • Definition: The movement of particles from areas of high concentration to low concentration • http://www.indiana.edu/~phys215/lecture/lecnotes/diff.html • http://www.biosci.ohiou.edu/introbioslab/Bios170/diffusion/Diffusion.html
Equilibrium • Molecules will continue to move until the solution reaches equilibrium • When is equilibrium reached when discussing cell membrane transport? • When the concentrations of particles are the same on both sides
Facilitated Diffusion • Particles flow from high concentration to low concentration but this time they need the help of proteins to get through the cell membrane.
Passive transport (cont.) • Osmosis • The diffusion of water across a selectively permeable membrane • Important in maintaining cell homeostasis • Water flows to side of membrane where the water concentration is lower until equilibrium is reached
Osmosis (cont.) • Osmosis is controlled by the amount of solutes on either side of a membrane
Remember, this is important, Osmosis deals with what? • The movement of particles • The movement of glucose • The movement of water • The movement of lipids
Cell Membrane Transport Notes (cont.) July 15, 2014
Osmosis – Types of Solutions • When dealing with osmosis, water can either move into the cell or out of it. • Sometimes the solute can not move to equal out the solution so the water has to. • We describe the solutions that cells are in as either hypotonic, isotonic, or hypertonic. 90% What are the concentrations? 40%
Isotonic Solution • Isotonic solution – Concentration of solute is the same in the cell and the area around the cell. • Give me an example of an isotonic solution that some of you use everyday
Hypotonic Solution • Hypotonic Solution – Concentration of solute is lower in the solution than in the cell. • Where is water going to move in order to reach equilibrium (Equal concentrations)? • Inside the cell
Hypotonic solutions • Since water moves into the cell the cell can explode • http://www.tvdsb.on.ca/westmin/science/sbi3a1/Cells/Osmosis.htm • So, Hypotonic solution, low concentration of solute, cell can explode
Hypertonic Solution • Hypertonic solution – concentration of solute is higher in the solution than in the cell. • Where is water going to move in order to reach equilibrium (Equal concentrations)? • Outside the cell
Hypertonic solutions • Since water moves out of the cell the cell will shrink • http://www.tvdsb.on.ca/westmin/science/sbi3a1/Cells/Osmosis.htm • So, Hypertonic solution, high concentration of solute, cell will shrink
Osmosis • http://www2.nl.edu/jste/osmosis.htm • http://www.coolschool.ca/lor/BI12/unit4/U04L06/rbc.html
The following diagram demonstrates what type of solution? = solute • Hypotonic • Isotonic • Hypertonic
In the following diagram which way is water going to move? = solute • Inside the cell • Outside of the cell • Both 1 and 2
The following diagram demonstrates what type of solution? = solute • Hypotonic • Isotonic • Hypertonic
In the following diagram which way is water going to move? = solute • Inside the cell • Outside of the cell • Both 1 and 2
Active Transport • Molecules move from low concentration to high concentration • Requires energy….why?
Other membrane transport activities that require energy • Endocytosis • Engulfing of large particles or liquids from outside the cell
2 types of Endocytosis • Phagocytosis • Engulfing of large particles from outside the cell • Pinocytosis • Engulfing of liquids from outside the cell
Other membrane transport activities that require energy • Exocytosis • Release of large particles or liquids from inside the cell Outside the cell Inside the cell
This diagram is an example of what membrane transport? • Diffusion • Facilitated diffusion • Endocytosis • Exocytosis
This diagram is an example of what membrane transport? • Diffusion • Facilitated diffusion • Endocytosis • Exocytosis