3A- Negative feedback occurs when some function of the output of a system, process, or mechanism is fed back in a manner that tends to reduce the fluctuations in the output, whether caused by changes in the input or by other disturbances.
3B- Negative feedback loops are used to maintain homeostasis and achieve the set point within a system. Negative feedback loops are characterized by their ability to either increase or decrease a stimulus, inhibiting the ability of the stimulus to continue as it did prior to sensing of the receptor.
Hope I’ve helped ;)
Answer: When you mix sand and water there are no reactions. The sand sits at the bottom of the water because the sand is heavier than the water is.
Evolution would be the answer you may be looking for.
The answer to your Q it is doubled rods of condensed chromatin
