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The point at which the polytene chromosomes appear to be attached is known as
(a)Centriole
(b)Chromocenter
(c)Centromere
(d)Chromomere

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Answer
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Hint Chromosomes are a part of genetic material which bind and condense the DNA molecule to maintain its integrity. They are thread-like structures which are located inside the nucleus of animal or plant cells and are made up of protein which passes from parents to their offspring.

Complete answer:
The point at which the polytene chromosome appeared to be attached is known as Chromocenter. Polytene chromosomes are large chromosomes that contain thousands of DNA strands. It provides a high level of function as salivary glands of insects and is present in dipteran flies, and a group of arthropods. it is also present in some mammalian trophoblasts. The repeated rounds of DNA replication produce polytene chromosomes without cell division and form giant chromosomes. It increases the volume of the cell nucleus and causes cell expansion which results in the metabolic advantage of multiple copies of genes that permits a high level of gene expression. Chromocenter is a region of a chromosome that retains the tightly spiralized structure between two successive cell divisions in the interphase. There appears to be a solid body under the microscope when stained with nuclear dyes.

Additional information:
Centriole: It is an organelle that is cylindrical and composed of proteins known as tubulin.they are found in eukaryotic cells and consist of a bound of pair of centrioles that are surrounded by a highly ordered mass of dense material known as the pericentriolar material that makes a centrosome. Centrioles are not present in all eukaryotes and are present in the male gametes of bryophytes, charophytes, vascular plants, and ginkgo. They consist of 9 sets of short microtubule triplets and include additional proteins such as centrin, testing, and calnexin and produce cilia during interphase and spindle during cell division.
Centromere: They are specialized DNA sequences which link a pair of sister chromatids and are attached to the centromere via the kinetochore during the mitosis. They have a highly complex multi-protein structure which is responsible for the chromosome segregation and signaling to the cell cycle machinery to correct the attachments to the spindle for cell division to proceed completion and enter anaphase.
Chromomere: They are beads or granules that results in local calling of a continuous DNA thread and also known as idiomere. They are formed in the areas of chromatin in the absence of transcription and condensing of DNA with protein complexes. During meiosis, chromomeres are present during the leptotene phase of prophase 1.

So, the correct answer is 'Chromocenter'.

Note: The number of chromosomes varies among every organism and they determine whether you are male or female. Bacterias consist of circular chromosomes and not all organisms consist of sex chromosomes. The X chromosome is always bigger than the Y chromosome and the human chromosome contains viral DNA.