Respiratory system= breathing system
To keep our Respiratory system healthy we should:
1- never breathe in front of polluted areas
2- never pollute our areas
3- try to make our environment normal
Carbon dioxide and water (and sunlight)
A dive instructor begins his leson on the shore as he guides his student out into the water what zone are they in
The group of organisms that occupy the second trophic level of an ecosystem is the herbivores
