The part of a cell which contain chromosomes?

Several billion years ago which gas was the least prevailant in the atmosphere

This is collection of data made by comparing objects in standard units. in science, the units are metric.

Been sitting here trying to take this test and don't know this answer! place the events of a feedback mechanism associated with body temperature in the correct order. ·nerve cells send message from skin to the brain ·body returned to normal temperature around 98.6 degrees f ·temperatures regulation center in the brain sends out signals ·body temperature exceeds 98.6 degrees f ·sweat glands throughout the body activate to cool off skin surface it is a 1 through 5 question in biology!