BIO 1201 GREGG EXAM 2 UPDATED

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BIO 1201 GREGG EXAM 2 UPDATED

ACTUAL EXAM WITH CORRECT SOLUTIONS.

transport proteins - correct answer- are responsible for controlling passage across the membrane

fluid mosaic model - correct answer- The membrane is a mosaic of protein molecules bobbing in a fluid bilayer of phospholipids

fatty acid tails - correct answer- nonpolar, hydrophobic

fatty acid heads - correct answer- hydrophilic, polar

periphial proteins - correct answer- bound to the surface of the membrane

integral proteins - correct answer- penetrate the hydrophobic core (ones that span the membrane are transmembrane protiens 1 / 3

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How do cells recognize each other? - correct answer- by binding to molecules, often containing carbohydrates, on the extracellular surface of the plasma membrane

Glycolipids - correct answer- Membrane carbohydrates that are covalently bonded to lipids.

Hypdrophobic - correct answer- molecules such as hydrocarbons that can dissolve in the lipid bilayer and pass through the membrane rapidly

Hydrophilic - correct answer- molecules that don't cross the membrane easily (ions and polar molecules)

transport proteins - correct answer- allow passage of hydrophilic substances across the membrane

carrier proteins - correct answer- bind to molecules and change shape to shuttle them across the membrane

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passive transport - correct answer- the diffusion of a substance across a membrane with no energy investment

Diffusuion - correct answer- Spreading out of particles away from each other, from an area of high concentration to an area of low concentration. (move to where space is available)

concentation gradient - correct answer- substances diffuse from high concentration----> low concentration

Osmosis - correct answer- Diffusion of water through a selectively permeable membrane

Isotonic - correct answer- when the concentration of two solutions is the same (no net movement)

Hypertonic - correct answer- cell losses water and shrivils

hypertonic - correct answer- cell gains water and expands

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