Answer:
D
Explanation:
Sexual reprduction is when a sperm cell fertilzes an egg cell.
72 chromatids were present in the present in the primary oocyte during prophase 1 of meiosis.
The primary oocyte contains 72 chromatids during prophase 1 of meiosis as the mature ovum has 18 chromosomes.
The primary oocyte contains 72 chromatids , that means it contains 144 chromosomes. During the first meiotic division, it produces one secondary oocyte and one polar body.
The secondary oocyte has 72 chromatids, which again undergoes second meiotic division and produces mature ovum and second polar body . The mature ovum contains contains 36 chromatids which means it has 18 chromosomes.
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Answer:
Nucleus (as nuclear DNA),mitochondrial(mitochondrial DNA) and chloroplasts.
DNA is packed tightly around protein called Histones, in Eukaryotes cells;so that many molecules can easily be held together as chromosomes.
Chromosomes are thread-like structure in nucleus of cells.The histones provide support to the DNA molecule
The part DNA molecule coded for by a polypeptide is GENE, therefore in the nucleus of cells, DNA contains GENE,and the gene and DNA are packed in chromosomes,DNA appears as circular DNA mitochondria
Explanation: