How do stem cells become specialized to absorb nutrients from food as intestinal cells?

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 of the following terms describe a liquid molecule that has only single bonds between its carbon atoms

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?