The answer is stem cells, they consist of classes of cells
that are undifferentiated and are able to be classified them into types like
specialized cells. They consist of having two main sources that will help them
develop and mature, these main sources are called the embryonic stem cell and
the adult stem cell.
 
        
             
        
        
        
Answer:
There are two possible answers: Deep-sea vents provided the energy needed for the first organic compounds to form OR self-replicating RNA molecules passed on genetic information.
Explanation:
The reason for the first answer is due to the hypothesis that indicates that life (organic molecules) arose from inorganic molecules synthesized from the amino acids in those energy vents. This is called the metabolism first hypothesis. The Miller-Urey Experiment provided evidence that organisms could rise from inorganic molecules (they simulated under the conditions you would see on early Earth). The second hypothesis is the RNA World hypothesis (second answer) which suggests that the formation of RNA that could replicate (possible due to mutation or evolution), led to life that could preserve its genetic integrity through replication (greater stability to the organism) and create lipid bi-layer membranes/other organelles. Some scientists support the Metabolism First Hypothesis, while others are skeptical (this goes for the RNA World Hypothesis as well). However, the RNA World Hypothesis is for more reasonable in the fact that its main point is the fact that RNA molecules were able to replicate and maintain genetic stability despite early Earth conditions. Although either hypothesis could explain why all organisms share the same genetic code, the RNA World Hypothesis better explains the universality of DNA/RNA of genes that we see today.
 
        
                    
             
        
        
        
During mitosis the chromosomes are being duplicated. which means the chromosomes that are formed during the mitosis is identical to its parents. during the mitosis, the cell udergoes 4 phases. prophase, metaphase, anaphase and lastly the telophase
        
             
        
        
        
Water is warmed by the sun and is evaporated. It is then cooled down and condensed. Finally, it is brought back to Earth in the form of water droplets (Rain)
I hope it helps!^^ May the power of unicorns be with you!