In the Northern Hemisphere, the summer solstice occurs on . A. June 20 or 21

B. March 20 or 21

A. June 20 or 21

Explanation:

In the Northern Hemisphere the summer solstice occurs on June 20 or 21 and the winter solstice on December 21 or 22. The situation is exactly... At the summer solstice, the Sun travels the longest path through the sky, and that day therefore has the most daylight.

before it leaves the nucleus of a eukaryotic cell, mrna is altered in the following ways: - a cap is added to the 5' end of the mrna molecule; - a poly a tail is added to the 3' end; - introns are removed and exons are spliced together.

an organism's phenotype is the  form of a trait  that it  displays. for  flowercolor, a pea  plant  can  display  a phenotype of purple or white flowers. an organism's  genotype  is the alleles of a gene it contains. based on his data, mendel concluded that a phenotype can be  determined  by more than one  genotype.