NEET BIOLOGY

CELL STRUCTURES AND FUNCTION

CELL DIVISION

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
What type of cell division has DNA copied before it happens?
A
Mitosis
B
Meiosis
C
Both
D
None of the above
Explanation: 

Detailed explanation-1: -Mitosis is a fundamental process for life. During mitosis, a cell duplicates all of its contents, including its chromosomes, and splits to form two identical daughter cells. Because this process is so critical, the steps of mitosis are carefully controlled by certain genes.

Detailed explanation-2: -DNA replication occurs during the S phase (the Synthesis phase) of the cell cycle, before mitosis and cell division. The base pairing rules are crucial for the process of replication. DNA replication occurs when DNA is copied to form an identical molecule of DNA.

Detailed explanation-3: -Definition. DNA replication is the process by which the genome’s DNA is copied in cells. Before a cell divides, it must first copy (or replicate) its entire genome so that each resulting daughter cell ends up with its own complete genome.

Detailed explanation-4: -DNA replication occurs in both mitosis and meiosis. In meiosis, the cell undergoes two divisions, i.e. meiosis I and II. Meiosis I is reduction division and meiosis II is similar to mitosis but DNA replicates only once during meiosis, i.e. before meiosis I in S phase.

Detailed explanation-5: -Before meiosis actually begins, the DNA that is packaged into chromosomes must be fully copied. Previous to replication, a germ cell contains two copies of each chromosome, a maternal copy, and a paternal copy.

There is 1 question to complete.