5-2 Active Transport

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5-2 Active Transport
The movement of materials against a concentration
gradient. (requires energy) Carrier Proteins
are involved in passive transport and Active
transport often they are called pumps because
they move molecules up their concentration
gradients.
High
Low
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Sodium-Potassium Pump
Na Concentration High
K Concentration Low
Na Concentration Low
K Concentration High
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Endocytosis

• is the process by which cells ingest external
  fluid, macromolecules and large particles
  including other cells.
• There are two types of endocytosis.

Vesicle membrane bound organelle formed from
the pinching of a sac in the membrane
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(No Transcript)
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a) Pinocytosis- transports into cell solutes or
fluids (Cellular drinking )
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b) Phagocytosis- Cellular Eating
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Exocytosis
The reverse of Endocytosis Cells release the
contents of their vesicles into the extracellular
environment. (like taking out the trash)
Inside Cell
Outside Cell
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1. Explain the difference between active transport
   and passive transport.
2. What functions do carrier proteins perform in
   active transport?
3. What provides the energy that drives the sodium
   potassium pump?
4. Explain the difference between pinocytosis and
   phagocytosis?
5. Describe the steps involved in exocytosis.
6. During intense exercise potassium tends to
   accumulate in the fluid surrounding muscle cells
   what membrane protein helps muscle cells
   counteract this tendency? Explain your answer.