Scientists have studied a fruit fly, Drosophila, to better understand early embryonic development and have discovered that the c
ell cycle changes as embryonic development proceeds. Model A represents the first 13 cell cycles after fertilization, which only includes two phases. Model B represents cell cycles 14 through 16, which are more complex and include a G2 phase. The figure shows two circular models, labeled Model A and Model B, that represent the cell cycle of fruit flies after fertilization. Model A represents cell cycles 1 through 13, and it contains two phases. Model B represents cell cycles 14 through 16, and it contains three phases. What of the following explains the advantage of a G2 phase during embryonic development?
A Cells can undergo the cell cycle more quickly with a G 2 phase.
B Cells can replicate more DNA with a G2 phase.
C Cells are checked for DNA damage before entering mitosis with a G2 phase.
D Cells are able to produce two new daughter cells with a G2 phase.
C. Cells are checked for DNA damage before entering mitosis with a G2 phase.
Explanation:
G2 phase is very important phase of cell division in which cells are checked for DNA damage before entering mitosis with a G2 phase as well as correct duplication of the DNA is also verified and cell proteins that are necessary for cell division are also produced. This phase comes after S stage in which replication of DNA occurs so this G2 phase check the damages before starting of mitosis.
The three main worm phyla are flatworms, roundworms, and segmented worms. Roundworms have a digestive tube that has two openings. Segmented worms have a closed circulatory system in which blood is enclosed in blood vessels. These are important steps in the evolutionary development of animals.
