types of cellular transport passive transport cell doesn’t use energy 1.diffusion 2.facilitated...
TRANSCRIPT
Types of Cellular Transport
Passive Transport
cell doesn’t use energy1. Diffusion2. Facilitated Diffusion3. Osmosis
Active Transportcell does use energy
1. Protein Pumps2. Endocytosis3. Exocytosis
high
low
This is gonna
be hard work!!
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low
Weeee!!!
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Facilitated Diffusion
*Is a type of passive transport
• Doesn’t require energy
• Uses transport proteins to move molecules from high to low concentration
Examples: Glucose or amino acids moving from blood into a cell.
• Facilitated Diffusion is the movement of larger molecules like glucose through the cell membrane – larger molecules must be “helped”
Proteins in the cell membrane form channels for large molecules to pass through
Proteins that form channels (pores) are called protein channels
outside of cell
inside of cell
Glucose molecules
Facilitated Diffusion
Facilitated diffusion
• Molecules move from high to low through a protein channel
• No energy is needed
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Active Transport
Requires energy or ATP
Moves materials from LOW to HIGH concentration
AGAINST concentration gradient
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Active transport
Examples: Pumping Na+ (sodium ions) out and K+ (potassium ions) in against strong concentration gradients.
Called Na+-K+ Pump
Active TransportActive transport is the movement of molecules from LOW to HIGH concentration.
Energy is required as molecules must be pumped against the concentration gradient.
Proteins that work as pumps are called protein pumps.
Ex: Body cells must pump carbon dioxide out into the surrounding blood vessels to be carried to the lungs for exhale. Blood vessels are high in carbon dioxide compared to the cells, so energy is required to move the carbon dioxide across the cell membrane from LOW to HIGH concentration.
outside of cell
inside of cell
Carbon Dioxide molecules
NO ENERGY NEEDED: Diffusion Osmosis Facilitated Diffusion
ENERGY NEEDED: Active Transport
ANALOGY:
Compare the types of transport
Food is moved into the cell by Endocytosis
Wastes are moved out of the cell by Exocytosis
• Endocytosis and Exocytosis is the mechanism by which very large molecules (such as food and wastes) get into and out of the cell
• **ENERGY IS REQUIRED
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Moving the “Big Stuff”
Molecules are moved out of the cell by vesicles that fuse with the plasma membrane.
Exocytosis- moving
things out.
This is how many hormones are secreted and how nerve cells communicate with one another.
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ExocytosisExocytosis vesicle immediately after fusion with plasma membrane.
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Endocytosis – Phagocytosis
Used to engulf large particles such as food, bacteria, etc. into vesicles
Called “Cell Eating”
Ex: White Blood Cells, which are part of the immune system, surround and engulf bacteria by endocytosis.