During fertilization, a haploid sperm cell unites with a haploid egg cell to form a diploid zygote, as shown below.
Which of the following diagrams shows how the zygote looks immediately following one cell division?

A. Y
B. X
C. W
D. Z

What are the two causes of density in deep current waters? a. salinity (how much salt) of the water and high temperaturesb. salinity (how much salt) of the water and low temperatures c. oxygen content of the water and high temperatures. d. oxygen content of the water and low temperatures