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.
Don't know
remaining cards
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

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


species a group of similar organisims.
variation difference between individuals of the same species.
evolution the process of modern organisims have descended from ancient organisims.
fossil preserved remains or traces of an organisim that has died.
adaptation inherited behaivor or characteristic that helps an organisim survive.
sientific theory well tested explanationfor a wide range of observations.
mechanisim something takes place naturally.
natural selection individuals that are more adapted are more likely to survive.
competition the struggle among living for things nessesary.
mutation any change to the genetic material.
fitness how well it can survive.
sexual selection acts on the ability possible to get the best mate.
coevolution two species evolve in response to changes over time.
fossil record fossils we have discovered and learned.
embryo young organisim that develops from a fertilized egg.
homologous structures similar structures that are inherited from common ancestors.
extinct does not exist or will never visit earth again.
protien organic material made from carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur.