Which activity happens during the m phase? 1.organelle copying 2. dna synthesis 3.chromatid joining 4. cell division

The correct answer is option 4 (cell division).

Explanation:

M phase also known as mitotic phase is a period of cell cycle which lasts for about 1 hour where cell divides its copied DNA and cytoplasm to form duaghter cells.

M phase is the dramatic phase of cell cycle where a sequence of observable cellular events takes place which can be divided into two phases-mitosis and cytokinesis.  

After completion of mitotic stages that is prophase, metaphase, anaphase, and telophase, cell proceeds for cytokinesis which begins with a little overlap with mitosis.

In cytokinesis, cytoplasm of the parental cell splits into two daughter cells completing cell cycle.

Thus, option 4 is the correct answer .  

the backbone of the dna and rna compound is sugar phosphate.

it takes hundreds of years to become stable.

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