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Answer:</h2>
<h3>1. Hepatitis B </h3><h3>2. Levels of circulating antibodies against a certain antigen.</h3>
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Explanation:</h2>
<h3>Hope its help</h3>
Gonadotropin-releasing hormone, luteinizing hormone (LH for short) and follicle-stimulating hormone (FSH for short).
EXPLANATION
When your body reaches a certain age, your brain releases a special hormone that starts the changes of puberty. It's called gonadotropin-releasing hormone, or GnRH for short. When this hormone reaches the pituitary gland, it releases two more hormones into the bloodstream: the LH and FSH. Although boys and girls do have these hormones, it depends on their sexual orientation the way these hormones work.
Answer:
Humans have some stem cells, but those cells are not easily available to help with healing. Most other mammals are the same, so they aren't good at regeneration either. Amphibians and some fish have stem cells that are more easily available, and are usually pretty good at regeneration.