Explain how thermoregulation operates under a negative feedback mechanism.

A negative feedback system is one that when it moves away from its desired state, acts to push itself back toward that state. Thus negative feedback is a method for maintaining stability. Thermoregulation is what the body does to maintain homeostatis, an (approximately) constant body temperature.

The answer is B. Nitrogen base

The sides of the DNA ladder are made of alternating sugar and phosphate molecules, the sugar being deoxyribose. The rungs of the ladder are pairs of four types of nitrogen bases (adenine, thymine, cytosine, and guanine)

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