Parasites are organisms that survive by harming anouther organism (feeding off of it, ex. tick, flea)
The statement above is false. The blood levels of calcium is regulated by parathyroid hormone.When one is not getting adequate calcium in one's diet and the blood level of calcium is low, the parathyroid hormone will be released. The parathyroid hormone can increase the blood calcium in several ways:
1. by stimulating osteoclasts which break down bone and release calcium into the blood stream.
2. by increasing the amount of calcium re-absorbed by the kidney before it can be excreted in urine.
3. by triggering the formation of calcitriol which increases the absorption of dietary calcium at the intestines.
Explanation:
Modern methods indicate that the mutation rate is roughly one to two mutation per 10,000 genes per generation.