diff --git a/Grade 9/Science/SNC1DZ/Study_Sheet.md b/Grade 9/Science/SNC1DZ/Study_Sheet.md
index 9082d18..c018989 100644
--- a/Grade 9/Science/SNC1DZ/Study_Sheet.md	
+++ b/Grade 9/Science/SNC1DZ/Study_Sheet.md	
@@ -399,7 +399,7 @@ efficiency varies from `5%` to `20%` energy available between successive trophic
 |:----|:----------|:------|
 |Water Cycle|Continuous movement of water on, above and below the surface of the Earth|<img src="https://www.noaa.gov/sites/default/files/styles/scale_crop_1120x534/public/thumbnails/image/watercycle_rc.png?itok=CcUyhuxd" width="800">|
 |Carbon Cycle|Main Pathway – in and out of living matter|<img src="http://climatechangenationalforum.org/wp-content/uploads/2014/09/carbon_cycle_1.jpg" width="700">|
-|Nitrogen Cycle|
+|Nitrogen Cycle|Main Pathway - In and out of plants and is helped by bacteria|<img src="https://i.pinimg.com/originals/95/e6/d2/95e6d2b0e43e826e2d811d894103d94e.jpg" width="700">|
 
 ## Water Cycle
 
@@ -450,8 +450,22 @@ atmosphere, river to lake)
 - <img src="https://image.slidesharecdn.com/lab-11methodsforestimatingdenitrificationprocess-130414125752-phpapp01/95/lab11-methods-for-estimating-denitrification-process-4-638.jpg?cb=1365944316" witdh="300">
 
 ### Nitrogen Fixation
-
-
+- Most of the nitrogen used by living things is taken from the atmosphere by certain bacteria in a process called `nitrogen fixation`. 
+- These microorganisms convert nitrogen gas into a variety of nitrogen containing compounds such as nitrates, nitrites, and ammonia
+- Lightning and UV radiation also fix small amounts of it
+- Humans add nitrogen to soil through fertilizer
+- 3 ways nitrogen to get fixed
+    1. Atmopheric Fixation
+    2. Industrial Fixation
+    3. Biological Fixation
+        - 2 types
+            1. Free living Bacteria
+                - Highly specialized bacteria live in the soil and have the ability to combine atmospheric nitrogen with hydrogen to make ammonium(NH<sub>4</sub><sup>+</sup>).
+                - Nitrogen changes into ammonium.
+            2. Symbiotic Relationship Bacteria
+                - Bacteria live in the roots of legume family plants and provide the plants with ammonium(NH<sub>4</sub><sup>+</sup>) in exchange for the plant's carbon and a protected biome.
+             
+    
 ## Benefits of Succession
 - Provides a mechanism by which ecosysmtems maintain their long term sustainability.
 - Allows ecosystems to recover from natural or human caused distrubances.