Save
Busy. Please wait.
or
show password
Forgot Password?
Don't have an account?  Sign up 
or
Username is available taken
show password

why


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.
focusNode
Didn't know it?
click below
 
Knew it?
click below
Don't know
Remaining cards (0)
Know
0:00
share
edit
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

gcse science B4 - H

specific for ocr gateway additonal science B.

QuestionAnswer
what is carbon dioxide? a compound containing carbon
how is carbon dioxide taken out of the atmosphere? by plants for photosynthesis. carbon is then passed along the food chain when animals feed
how is carbon dioxide put back into the atmosphere? -plants and animals which respire -fungi and bacteria which respire when they decompose -burning fossil fuels such as coal and oil -erupting volcanoes and forest fires
how is carbon recycled at sea? -shells of marine organisms (e.g. molluscs) contain carbonates. -when they die, their shells turn into sedimentary rock called limestone -limestone is attacked by acid rain, giving off carbon dioxide
how much nitrogen is in the atmosphere? 78%
why do plants and animals need nitrogen? to make proteins for growth
why can't plants and animals use nitrogen directly? its inert - unreactive
how does nitrogen get into plants? in the form of nitrates
how do decomposers contribute to the nitrogen cycle? they break down proteins in dead bodies and urea into ammonia
how do nitrifying bacteria contribute to the nitrogen cycle? they convert ammonia into nitrates
how do nitrogen-fixing bacteria contribute to the nitrogen cycle? they 'fix' nitrogen by converting it into ammonia or nitrates and then into amino acids to form proteins
how does lightning contribute to the nitrogen cycle? fixes nitrogen by combining nitrogen and oxygen to form oxides. the oxides dissolve in rain and form nitrates in the soil
how do denitrifying bacteria contribute to the nitrogen cycle? convert nitrates back into nitrogen gas
Created by: jirwin
 

 



Voices

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:
Retries:
restart all cards