Answer:
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.
The answer could possibly be natural selection or survival of the fittest
June 21st represents the sun in the sky at noon for the northern hemisphere.
Explanation:
The summer is hotter because the sun's part is higher in the sky. This reason makes the days longer and makes summer sun more intense.
The summer solstice for northern hemisphere occurs in june 21. On this day the sun's position at noon is higher in altitude of the year.
In the summer season , The north pole is tilted towards the sun and this causes the sun's part to be higher in the sky causing the northern hemisphere to receive more light and heat.