DIFFUSION Flashcards
Is diffusion active or passive
passive
What is passive transport
exchange of substances that do not require metabolic energy
What is active transport
exchange of substances that require metabolic energy
Where does passive transport get their energy from
the natural, in-built motion of particles
Are all particles constantly in motion and why
yes because of the kinetic energy that they possess
What type of motion do the particles move in
random
What is diffusion
the net movement of molecules or ions from a region where they are more highly concentrated to one where their concentration is lower until evenly distributed
Why can oxygen and carbon dioxide diffuse through simple diffusion
they are small so can pass through spaces between the phospholipids, and non-polar so they are soluble in lipids which means they can dissolve in the hydrophobic bilayer
What is simple diffusion
when molecules diffuse directly through a cell membrane
What is facilitated diffusion
the movement of charged ions and polar molecules with the help of carrier and protein channels
Where does facilitated diffusion get its energy from
the in-built motion (kinetic energy) of the diffusing molecules
What are the 2 types of protein involved in facilitated diffusion
ptorain channels and carrier proteins
What do protein channels form
water-filled hydrophilic channels across the membrane
What do protein channels allow
specific water-soluble ions to pass through the membrane
When do protein channels open
in the presence of specific ions
