Mixed Short Biology Essays.

1.Regulation is the life process by which organisms and cells respond to our constantly changing internal and external environment. This is important because an upset in homeostasis in any one of an organism's systems might result in an imbalance in the organism's homeostasis. In humans, regulation consists of the endocrine and nervous systems. The endocrine system is made up of many organs that produce hormones into the bloodstream. The nervous system carries messages in the …

…passive immunity is only temporary, active immunity is long-lasting. 14.Negative feedback is a chemical response to chemical regulation of glandular secretions that opposes the original change. The level in one hormone in the blood stimulates the production of another hormone. An example of negative feedback is if the concentration of thyroid hormone in the blood drops below a certain level, the pituitary is stimulated to produce TSH which stimulates the production of more thyroid hormone.