Answer:
Chitin
Explanation:
 This glucose derivative is in fact the main building block of cell walls in not only arthropods (including the shrimp), but also fungi and insects, and also has a structural function in the scales of fish. The most similar commonly-known substance in terms of function is keratin, which makes up our hair and nails.
 
        
                    
             
        
        
        
Answer:
Exercise is important for the body to function properly.
Explanation:
Exercise helps a person to maintain the oxygen amounts in the body. Exercise, as such, enhances and regulates almost every system of the body including the nervous, respiratory, circulatory and hormonal systems. 
The sympathetic division of the autonomic nervous system controls the physical activities in a person's body by detecting the low levels of oxygen and increasing amounts of carbon dioxide in the body. 
 
        
             
        
        
        
Answer:
All living things
Explanation:
Climate affects everything
 
        
             
        
        
        
Answer:
Alpha-1
Explanation:
Adrenergic receptors are the integral proteins present in the postsynaptic plasma membranes. These receptors are activated when the neurotransmitter norepinephrine and the hormones norepinephrine and epinephrine bind to them. The alpha 1 adrenergic receptors are found in the smooth muscle fibers of blood vessels that serve the salivary glands, skin, and kidneys. These receptors are also found in the radial muscle of iris of the eye as well as in the sphincter muscles of the stomach and urinary bladder. 
They exert excitatory effect and lead to contraction of smooth muscles of the blood vessels, dilation of pupil, and closure of sphincters of the bladder.