The statements are true.
Hemoglobin (Hb), is the oxygen-transport metalloprotein which contains iron in the centre of its structure. This metalloprotein is found in the red blood cells (erythrocytes). The function of hemoglobin is to transport the oxygen through the blood carries from the lungs to the rest of the tissues. Oxygen is necessary for the aerobic respiration in order to provide energy for the functions of the organism (metabolism).
 
        
             
        
        
        
The most likely result is that in such conditions would be the reduction in the number of animals, plants and fishes that were in water. 
        
                    
             
        
        
        
The correct answer is A. Saguaro Cacti, with the scientific name <span>Carnegiea gigantea, </span>which is very significant biotic feature to the Sonoran Dessert's ecosystem. The craziest fact about it is that it can grow up to 40 feet tall! The Sonoran Desert is a North American dessert, also. Some other critical biotic features of this desert include joshua trees, rattle snake, and red-tailed hawk. 
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                  - Dotz