At what point in the cell cycle does DNA replication occur and why?
A. before a cell divides, to provide each of the two resulting cells with a complete set of DNA
instructions
B. before a cell divides, to ensure that the DNA will fit into the resulting cells
C. during cell division, to ensure that the DNA will fit into the resulting cells
D. after a cell divides, to provide each of the two resulting cells with a complete
set of DNA instructions

DNA replication is the process in which DNA forms a copy of itself during cell division.

DNA replication occurs:

Cell division is the process in which cell is divided to produce daughter cells. The main parts of cell division are:

DNA replication occurs prior to the division of the cell. During the interphase or resting phase of the cell, the DNA is replicated via a replication fork.

The mechanism involves the making of a complementary sequence of parent DNA. This DNA is then transmitted to the daughter cells via cell division. The DNA in the daughter cells is the exact copy of the parent DNA.

The mitosis or M phase is the stage in which replicated DNA is distributed in the daughter cells.

Therefore, option A is correct.

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A. before a cell divides, to provide each of the two resulting cells with a complete set of DNA

instruction

Explanation: DNA replication occurs at the s phase of the interphase. It is process in which a new copy of DNA strand is made. The existing DNA strands serves as template for the new one. We have conservation and semi-conservative replication.

DNA replication occur before cell divides because the new daughter cell contain the exact copy of the original DNA.

regulation of gene expression. gene expression can be regulated by various cellular processes with the aim to control the amount and nature of the expressed genes. these regulatory proteins bind to dna and send signals that indirectly control the rate of gene expression

explanation:

c. heat from the poles back down towards the equator.