<span>the way a mineral cleaves reveals its crystal structure. true.
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<span>By definition, a mineral must have a crystal structure.</span>
The hormone described above is the hormone Melatonin.
Melatonin is a hormone secreted by the pineal gland in the brain, which helps regulate other hormones and maintains the body's circadian rhythm. This rhythm is an internal 24 hour clock that plays a critical role when we fall asleep and when awake. When it is dark the body releases more melatonin.
Theres your answer look at the photo
