Galaxy is a collection of stars, gas, and dust bound together by gravity. The smallest galaxies may contain only a few hundred thousand stars, while the largest galaxies have thousands of billions of stars.
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For ectotherms, on the other hand, body temperature mainly depends on external heat sources. That is, ectotherm body temperature rises and falls along with the temperature of the surrounding environment. Although ectotherms do generate some metabolic heat—like all living things—ectotherms can't increase this heat production to maintain a specific internal temperature.</span>
The correct option is this: PROTO ONCOGENES BECOMES ONCOGENES.
Proto oncogenes genes are those genes that regulate the process of normal cell division in the living system. These cells starts cell division when necessary and terminate the cell division when the necessary cells have been formed. When these genes lose the power to regulate cell division, the cells continue to divide indefinitely without stopping and this leads to a medical condition called cancer. At this stage, the proto oncogenes have been turned into oncogenes, which are genes that caused uncontrolled cell cycle divisions.