Transcript Chapter 19 : Cycles in Nature

Chapter 19 : Cycles in
Nature
Ms. Epps and Ms. Arrington
AC Science 7th grade
http://www.youtube.com/watch?v=fm5RvtL
D0xI
http://www.youtube.com/watch?v=P_ru5UnrUTs
Nitrogen Cycle!!
Organisms need nitrogen to build proteins and DNA for
new cells.
This cycle is the movement between the environment
and living things.
78% of the Earth’s atmosphere is nitrogen gas – HOLY
COW!
Most organisms can’t use nitrogen gas DIRECTLY so the
bacteria in the soil converts it into forms that plants can
use – Nitrogen Fixation
When organisms die, decomposers break down the
remains, which releases a form of nitrogen
Virtual Investigation!!
Go to the link below.
Answer the questions on your lab sheet.
http://www.pbslearningmedia.org/content/lsps07.sci.life.eco.nitrogen/