1inch 2cm 8ft have a nice day and 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.
I believe the correct answer would be <span>variation. The definition of variation in biology means,</span><span> any difference
between cells, individual organisms, or groups of organisms of any
species caused either by genetic differences or by the effect of environmental factors on the expression of the genetic potentials. So i think that organisms can also be classified as variation. Hope this helped. ♥ ☺
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Because of its ability to form large complex and diverse molecules
The kidneys.
The kidneys keep blood isotonic by removing excess salt and water through urine.
