Climacteric is one of the most important physical changes of midlife that occurs in the reproductive system as fertility declines. It is the time in most women's lives when menstrual periods stop permanently. The fertility and the sexual activity are in decline.
They may want an organism of a certain trait suits a pet or for household security. Therefore will breed the best of these lines for these specific traits. Humans may want a pet to be mild, furry, small, and cute. For security, humans will prefer fierce, big and tenacious traits in an organism.
The neuroendocrine system produces and releases hormones which are basically chemicals that travel via the bloodstream to specific organs in the body to control things like heart rate, glucose release rate, etc. This is how homeostasis in maintained.
C) Both.
Plants go through photosynthesis (producing Oxygen), but to consume the sugars they have created they have to go through cellular respiration as well, which produces carbon dioxide. All organisms go through cellular respiration.
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