Answer:
All the above
Explanation:
I'm not 100% sure this is accurate. Good Luck!
 
        
             
        
        
        
Heart rate is controlled by the two branches of the autonomic (involuntary) nervous system. The sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). The sympathetic nervous system (SNS) releases the hormones (catecholamines - epinephrine and norepinephrine) to accelerate the heart rate. The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate. Such factors as stress, caffeine, and excitement may temporarily accelerate your heart rate, while meditating or taking slow, deep breaths may help to slow your heart rate.
        
             
        
        
        
Answer:
takes in carbon dioxide, puts out oxygen
Explanation:
 
        
             
        
        
        
There is 20 chromosomes in a adult wild mouse
        
                    
             
        
        
        
Hello. 
The subatomic particles located inside of the nucleus of an atom consist of protons and neutrons.