Answer: Option [C]Each chromosome at the anaphase stage of a bone marrow cell in our body has only one chromatid. A normal chromosome has only 2 chromatids, During anaphase, the chromosome splits and forms new chromosomes or daughter chromosomes, these chromosomes have only one chromatid.
Answer: Option [C]A complete set of chromosomes inherited as single unit from one aprent is known as genome. The genome is the genetic material of an organism. It is encoded either in DNA or, for RNA viruses, in RNA. The genome includes both the genes and the non-coding sequences of the DNA or RNA. A genome is an organisms complete set of DNA, including all of its genes. Each genome contains all of the information needed to build and maintain that organism. In humans, a copy of the entire genomemore than 3 billion DNA base pairs is contained in all cells that have a nucleus.
Answer: Option [C]Centromere is a part of chromosome which helps in the movement of chromosomes. Centromere joins the microtubules of 'Chromosomal spindle fibres and helps in the movement of chromosome during cell division. Centromere also plays an important role in the polymerization of tubulin protein used in the formation of microtubules. Hence it is helpful in attaching the chromosome with spindle fibres.
Answer: Option [B]The puffs and rings are associated with the polytene chromosomes. Polytene chromosomes are over-sized chromosomes which have developed from standard chromosomes and are commonly found in the salivary glands of Drosophila melanogaster. During their initial stages of development these bands or interbands of the chromosomes exhibit swellings or puffs. The RNA of puffs is also not similar; it differs from each other in chemical composition. Some regions show larger puffs than others. These larger puffing regions are called Balbiani rings.
Answer: Option [A]Lampbrush chromosomes are visible in diplotene of meiosis. Homologous chromosomes begin to separate but remain attached by chiasmata. Synaptonemal complex degrades and the chromosomes separate from one another, a small amount giving this appearance. It is possible that some chromosome uncoiling may also occur allowing some gene transcription. Lampbrush chromosomes are visible during this stage.