What organ serves as the control center for the regulation of erythropoiesis?

Which of the following would most likely be key to gathering evidence that the rna world hypothesis is valid? creation of suitable environments for long-term study of single-celled organisms simulation of early earth conditions and long-term study of the resulting molecules development of a system for studying the microsphere's ability to absorb additional molecules categorization of the different specific conditions that result in the development of microspheres

Which statements about the enhanced for loop are true for arrays of primitive data?

Asnail, elodea (aquatic plant), or both were added to the tubes and they were stoppered. tubes were placed under a grow light for 24 hours and the results recorded. the test tubes were then covered for 24 hours to produce a dark environment and the results recorded. which statement best explains the change in test tube d from the light setup to the dark setup.