Homeostasis & Transport Flashcards
Cell membrane
A boundary between the cell and its environment.
What is the bilayer composed of?
PHOSphoLIPiDs.
TRUE or FALSE: The plasma membrane controls what goes in and out of the cell.
true
Explain what exactly is “selective permeability”?
It refers to the membrane’s ability to differentiate between different types of molecules, only allowing SOME MOLECULES through while blocking others.
How are proteins helpful in the cell membrane?
They help move LARGE MOLECULES and NON-POLAR substances through the membrane.
What is diffusion?
A. Movement of particles down their concentration gradient into / out of the cell with the help of a protein (no ATP used)
B. Movement of water down the concentration gradient into / out of the cell without using ATP
C. Movement of particles down their concentration gradient into / out of the cell without using ATP
C. Movement of particles down their concentration gradient into / out of the cell without using ATP
Osmosis is the ________ of water down the _____________ gradient into/out of the ____ without using ___.
Osmosis is the MOVEMENT of water down the CONCENTRATION gradient into/out of the CELL without using ATP.
TRUE or FALSE?: Facilitated diffusion moves particles up in the concentration gradient with the help of ATP.
FALSE!!! It is the movement of particles down their concentration gradient into / out of the cell with the help of a protein (no ATP used)
Can larger/polar particles get through the phospholipid bilayer?
no
GUESS THE VOCAB: What is the state when molecule concentration is equal across the membrane?
dynamic equilibrium.
GUESS THE VOCAB: Movement of molecules through the cell membrane using ATP.
ACTIVE Transport .
In which direction are particles moving in active transport?
LOW to HIGH concentration. (which is against their concentration gradient.)
Are endocytosis & exocytosis examples of passive transport?
No, they are examples of active transport because they allow larger molecules that cannot diffuse through the lipid bilayer to cross the membrane. All of which require energy (ATP).
Which type of “cytosis” is is the movement of large molecules INTO the cell.
ENDOcytosis.
Exocytosis is the ________ of large _________ out of the cell using a _______.
Exocytosis is the MOVEMENT of large MOLECULES out of the cell using a VESICLE.
