Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Didn't know it?
click below
Knew it?
click below
Don't know
Remaining cards (0)
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Chapter 4

Basic Unit of Life

ATP Adenosine triphosphate; a molecule in all living cells that acts as fuel
hormone a chemical signal used to control body function
microscope an instrument used to magnify things
cell theory a theory that all living things are made of cells, that cells are the basic units of structure, and that cells only come from already present cells
homeostasis the ability of organisms to maintain their internal conditions
transport to move molecules from one side of a membrane to the other
concentration a measurement of the amount of dissolved substance in a fixed amount of solvent
diffusion the movement of molecules from an area of high concentration to an area of low concentration
selectively permeable membrane a membrane that allows some molecules to pass but blocks other molecules from coming through
concentration gradient a difference in the concentration of a substance across a distance
osmosis the movement of water through a cell membrane
hypotonic a solution whose solute concentration is lower than the solute concentration another solution
solute a dissolved substance
hypertonic a solution whose solute concentration is higher than the solute concentration of another solution
isotonic a solution whose solute concentration is equal to the solute concentration of another solution
equilibrium a state where concentration are equal in all parts of an area
prokaryote a cell with only one outside membrane and no nucleus or other internal structures
binary fission reproduction in which a bacterial cell divides into two sells that look the same as the original cell
eukaryote a cell with several internal structures, including the nucleus, that are surrounded by membranes
organelle a tiny membrane-bound structure inside a cell
tissue a group of cells that are similar and work together
epithelial cell a skin cell
nervous tissue nerves made from collections of nerve cells
organ a group of different tissues that work together to perform specific connected tasks
organ system a group of organs that work together to perform specific connected tasks
circulatory system a collection of organs, including the heart, which moves blood and gases throughout the body
Created by: mrspuffisphat21



Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards