Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

13 Cards in this Set

  • Front
  • Back
Diffusion Across Membranes
*chemical/electrical gradient
*simple diffusion, channel, carrier
*diffusion - all directions - net diffusion(high to low concen)
*membranes are semi-permeable
Diffusion Across Membranes
*(things that hate water)
*fat soluble
*fats-fatty acids, cholesterol, steroids
*fats-bound to transport molecules in ECF, ICF, protein, etc.
*gases(O2, CO2) - fluidity - O2 helps transport across membrane easy
Diffusion Across Membranes
*small objects diffuse across easier then large objects
*H2O, urea->only things small enough to cross
*proteins large and hydrophilic ONLY cross by excocytosi or endocytosis, depending on which way they're going
Fick's Law of Diffusion
*measures rate of diffusion
Ion Channels
*Types: Na+, K+, Ca+, Cl=
*both electrical and chemical gradients are important
*diffusion of water
*move things from high h2o concentration to low h2o concentration
*higher h2o concentration, lower solute concentration.
*lower h2o, higher solute
Carrier Transport
*carry hydrophilic substances across
*sugars, amino acids, ions
*driven by chemical graients or the use of ATP
Carrier Transport
*each carrier moves specific molecular type or ion
Carrier Transport
*limited # of carriers in a membrane
*Tm - transport maxiumum-the fastest rate, when all carriers are used
Carrier Transport
-Facilitated Diffusion
*no ATP
*chemical gradient which drives them
*molecule binds to carrier, more on high concen. side-movement is to low concen. side
Carrier Transport
-Active Transport
*use ATP to change carrier affinity(how likely they are to bind) for ion
*movement from low concen. to high concen.
*create ion gradients across membrane
Carrier Transport
-Active Transport
-Na-K ATPase
*sodium pump
*pumps Na+ out of cell, pumps K+ into cell
*store energy in Na+ and K+ gradients
Secondary Active Transport
*use Na+ molecules to exchange things
*carrier moves Na+ into cell: sugar/amino acid
*Ion/Ion exchange-> K+/H+, Na+/Ca+ exchanges/cotransported