Answer:
Option (A).
Explanation:
Muscle contraction may be defined as the physiological process of the activation of tension generating sites that occur within the muscle fibers. Actin, myosin, troponin and other proteins are important for muscle contraction.
The calcium ion is important for the muscle contraction. The binding of calcium with troponin causes the movement of tropomyosin out of the grooves between the actin molecules during muscle contraction.
Thus, the correct answer is option (A).
 
        
                    
             
        
        
        
Answer:
breathing
Explanation:
because the polluted air from factory mix into the air and then to the plants and the animals breathe the air
can i have brainlist please
 
        
                    
             
        
        
        
<span>Normal urine is usually pale yellow to amber in color, due to the presence of Urochrome!</span>
        
                    
             
        
        
        
Explanation:
Solids:
Particles stay close together with a pattern 
Particles do not flow freely
Definite shape and definite volume
Liquids:
Particles are closer together (compared to gas) with somewhat of a pattern
Particles flow freely
Somewhat strong attractive forces that hold an indefinite shape
Gas:
Particles spread out without a pattern
Particles flow everywhere (they are like kids on a sugar rush)
Weak attractive forces that hold no shape or volume
Indefinite shape and indefinite volume
Not entirely sure what compressibility is so i skipped that one for all of them