Review for Cell Membrane Structure Molecular Movement Quiz

Review for Cell Membrane Structure & Molecular Movement Quiz!

Cell Membrane Selectively Permeable Controls what goes into and out of the cell! Outside Cell Inside Cell Nonpolar

Cell Membrane Polar = Hydrophilic → Water Loving Nonpolar = Hydrophobic → Water Fearing

Polar phosphate group Nonpolar tail

What is the cell membrane made of? • • Phospholipid Bilayer (polar head & nonpolar tail) Proteins Cholesterol Carbohydrates (attached to phospholipids & proteins)

Cell Membrane What are ions? Name a polar molecule The cell membrane blocks… -All Ions (charged molecules) -Most polar molecules -Large molecules

Cell Membrane The cell membrane does NOT block… • Nonpolar molecules • CO 2 • O 2

How do the molecules blocked by the cell membrane get through? ? ?

With the help of proteins embedded within the cell membrane!

Passive Transport Osmosis & Diffusion

Passive Transport • Process moving materials across the plasma membrane • Does not require energy from the cell!!! • Materials move down the concentration gradient: high concentration → low concentration • 3 Kinds: Diffusion, Osmosis, and Facilitated Diffusion

Diffusion • The movement of small, non-polar molecules across a membrane • Molecules move from areas of high concentration to areas of low concentration (molecules “spread out”)

Diffusion Wh occ at w pic ur in ill ture the rela belo w t i v , e diff usi to on?

-Solutes move from a location of high concentration to low concentration. -Solutes reach equilibrium

Osmosis • Diffusion of water across a selectively permeable membrane. • Water moves from high concentration to low concentration.

osmosis Wh occ at w pic ur in ill ture the rela belo w t i v osm e to , osi s?

-Water move from a location of high concentration to low concentration. -Solution reaches equilibrium

Facilitated Diffusion • Movement of large or polar molecules through transport proteins • Molecules move from high concentration to low concentration Does it require energy?

Active transport • Moves large, polar, or charged molecules through transport protein • Moves from areas of low concentration to high concentration • Requires energy!!

Active transport Important Example: • Sodium-Potassium Pump: This is how your nerves send signals!

Review the following table!!

Membrane Transport Types Animation Watch this really good animation about the types of transportation across a cell membrane! https: //www. youtube. com/watch? v=jods 4 dg. Y_JI

https: //www. youtube. com/watch? v=d. PKv. Hr. D 1 e. S 4