EMBRYOLOGY
CHROMOSOMES AND CELL DIVISIONS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the cell grows
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the nucleus divides
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the cell membrane divides
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the DNA is replicated
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Detailed explanation-1: -G1 is followed by S phase (synthesis), during which DNA replication takes place. The completion of DNA synthesis is followed by the G2 phase (gap 2), during which cell growth continues and proteins are synthesized in preparation for mitosis.
Detailed explanation-2: -S Phase. Throughout interphase, nuclear DNA remains in a semi-condensed chromatin configuration. In the S phase (synthesis phase), DNA replication results in the formation of two identical copies of each chromosome-sister chromatids-that are firmly attached at the centromere region.
Detailed explanation-3: -During the S phase, the chromosomes enter a relaxed state that allows the enzyme DNA polymerase to access the DNA double helix inside each chromosome. Replication begins when helicase enzymes unzip various locations along the chromosome, separating the two complementary strands of DNA.
Detailed explanation-4: -The entire meiosis cell cycle has only one S phase that means the DNA will get replicated only once in the entire meiotic division.