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.
Explanation:
(1) The conglomerate contains some nonsedimentary rock fragments. (2) The conglomerate was formed from material that was buried deep underground. (3) The conglomerate's pebbles are all weathering at the same rate.
1.) similar fossils were found on different continents.
2.)the continents seemed to fit together; they were like a spread apart puzzle.
3.)geographical features and mountain ranges lined up with the same rock composition
4.)glacier grooves in rocks led him to trace them out to where they started
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