Cell Membrane/Cell wall

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Cell Membrane/Cell wall

• SC.912.L.14.2

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Essential Questions

• How does something as thin as a cell wall or
  membrane protect a cell?

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Cell membrane and Cell wall

• Among the most important parts of a cell are its
  borders, which separate the cell from its
  surroundings.
• All cells are surrounded by a thin, flexible
  barrier known as the cell membrane.
• Many cells also produce a strong supporting layer
  around the membrane known as a cell wall.

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What type of barrier?

• The cell membrane is not like a like a ziploc
  bag.
• It is constructed so that certain small
  molecules, like water, can move easily in and out
  of the cell.
• Other larger molecules have special protein
  channels that allow them entrance.
• Special pumps control the amounts of some
  substances.

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How do substances enter and exit a cell?

• Osmosis
• Diffusion
• Facilitated Diffusion

• Endocytosis
• Exocytosis
• Pinocytosis
• Phagocytosis
• Transport Pumps

• Active Transport
• Requires the cell to use energy (ATP)
• From low concentration to high concentration
  (Uphill)

• Passive
• No energy (ATP) required
• From high concentration to low concentration (
  Downhill)

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Day 2 Animations

• Exocytosis
• Active and Passive Transport
• Pinocytosis