In a human, only the β cells of the pancreas make insulin and only the chief cells of the stomach make pepsinogen (an inactive f
orm of the main digestive enzyme pepsin). This is most likely because: a. Only the DNA of β cells contains the gene for insulin; only the DNA of chief cells contains the gene for pepsinogen
b. A different combination of control elements is found within enhancers associated with the insulin vs. pepsinogen genes
c. β cells and chief cells will synthesize the combination of activator proteins specific for the enhancers of the insulin and pepsinogen genes, respectively
a. Only the DNA of β cells contains the gene for insulin; only the DNA of chief cells contains the gene for pepsinogen
Explanation:
As stated in the question above, insulin production is exclusive to β cells in the pancreas. This is because only these cells have a gene that manages the production and excretion of insulin within an organism. Similarly, only the main cells of the stomach have the capacity to produce pepsinogen, which indicates that the gene responsible for managing this production is unique to these cells.
There are three things.... The margins of the drifting continents, the existence of matching rock types and formations and the presence of similar fossils on opposing edges!
John Hartë made an observation that a steady decrease in the tiger salamander (Ambystoma tigrinum nebulosum) population was caused due to the increased acidity in ponds. He had found that melting snow can release a pulse of acidity that damages salamander eggs.
