Like this study set? Create a free account to save it.

Sign up for an account

Already have a Quizlet account? .

Create an account


(how it works)
study of biological function


ability to maintain constant internal balance regardless of the environment (steady state)
-occurs at all levels
-cells exist in fluid environment
-cells must keep cytoplasm

4 factors decide what go through (homeostasis)

-cell membrane
-dissolves in water
-conditions inside & outside the cell

At cellular level, homeostasis depends on movement....

in & out of the cell
-all things must pass through cell membrane


can pass through


can't pass through

cell membrane is....

selectively (chemical) and semi-permeable (size, charge)

passive transport

energy is not required for substances to pass in and out of the cell


moving particles from high to low concentration
-possible because of kinetic energy (energy of motion) atoms move in a straight line
-atoms keep moving til their spread evenly

Factors that affect rate of diffusion



movement of water (diffusion)
-call can't control osmosis - it moves on it's own

isotonic solution

some inside & out
-no net water movement

hypertonic solution

higher outside the cell
-water moves out

hypotonic solution

lower outside the cell
-water moves in

tugor pressure

pressure exerted by cell contents against the cell wall
-helps support soft tissue


loss of tugor pressure
-causes cell contents to shrink away from the cell


bursting of cell from water pressure inside

active transport

energy required, low to high.


moves molecules and particles into the cell
-phagocytosis - cytoplasm surrounds the particles
-pinocytosis-collects on the cell membrane and pinches inward


large particles shipped out by golgi apparatus

Passive & active transport...

of materials through the cell membrane are ways cell maintains homeostasis

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

Voice Recording