question number 7.

Photosynthesis is autonomic process. The autotroph possess plastids. Plastids have 3 kinds of compound. Chlorophyll itself a cell. It is a type of constructive metabolism which formed energy packet via sunlight.

Respiration is a destructive type of metabolism. The aerobic type of respiration take place in mitochondria. It re-bond elements of food. So Release ATPz .these are required for working.

Nitrogen cycle.

The ratio of nitrogen is maintained constant in environment through cyclic activities ,this maintenance process is termed as nitrogen cycle. It revolve around nitrifying bacteria,photosynthesis,respiration and de nytrifyning bacteria. So after being consumed nitrogen go backs to atmosphere.

__________________
"Wa tu izzu man-ta shaa, wa tu zillu man-ta shaa"