Answer:
chemical reactions change reactant and produce new substance called products.
Explanation:
chemical reaction is a change which will produce a new substance. ( while physical reaction does not produce a new substance.
Answer:
The answer is when the cell express different genes.
Explanation:
Cell differentiation is the process when a cell is changed from one cell type to an other and brings more complexity to the system. A cell before differentiation possess all the genes however their expression in turned off. When some external or internal factors trigger the gene expression it starts the cell differentiation. A multicellular organism undergoes several rounds of cell differentiation during its development. Although cell differentiation changes the size, shape and metabolic activity but the genetic makeup or DNA is never changed during cell differentiation.
C. <span>eukaryotic cells contain organelles that are enclosed in membranes.</span>
Electricity, heat and fuels.
<span>s that a single on off switch can control the whole cluster of functionally related genes; these genes are coordinately controlled (ex: when Ecoli must make tryptophan for itself because the nutrient medium lacks this amino acid all the enzymes for the metabolic pathway are synthesized at one time)</span>