1)centriole form aster rays not centromere so 1 option incorrect
2)only pancreas cell synthesize insulin not all body cell so 2 option incorrect
3)nucleosome are formed histone octomers around nucleotide not by nucleotide so 3 option incorrect
4)nucleosome is made of histone octamers so 4 is correct
I think so

Centromere is found in animal cells, which produces aster during cell division.

The statement is incorrect. The centromere is a region of DNA found in eukaryotic cells that plays a crucial role in cell division. It is responsible for the attachment of the spindle fibers during mitosis and meiosis, which ensures the proper segregation of chromosomes into daughter cells. While aster is indeed produced during cell division, it is not directly related to the presence of the centromere.

The gene for producing insulin is present in every body cell.

The statement is incorrect. The gene for producing insulin, known as the INS gene, is not present in every body cell. Insulin is a hormone produced by specialized cells in the pancreas called beta cells. These beta cells contain the INS gene, which codes for the production of insulin. Other cells in the body do not have this gene and therefore do not produce insulin. However, most cells in the body have insulin receptors on their surface, allowing them to respond to insulin and regulate glucose uptake and metabolism.

Nucleosome is formed of nucleotides.

The statement is incorrect. Nucleosomes are not formed directly from nucleotides but are structural units composed of DNA and proteins called histones. Nucleotides are the building blocks of DNA, while nucleosomes are formed by wrapping DNA around histone proteins. Each nucleosome consists of a core of eight histone proteins (two copies each of histones H2A, H2B, H3, and H4) around which approximately 147 base pairs of DNA are wrapped. This DNA-histone complex forms the basic unit of chromatin, the condensed structure of DNA in the cell nucleus.

DNA consists of a core of eight histones.

The statement is incorrect. DNA does not consist of a core of eight histones. DNA is a double-stranded molecule made up of repeating units called nucleotides, which consist of a sugar, a phosphate group, and a nitrogenous base. Histones, on the other hand, are proteins that associate with DNA to form nucleosomes and help in the packaging and organization of DNA in the cell nucleus. As mentioned earlier, a nucleosome consists of a core of eight histone proteins, around which DNA is wrapped. However, DNA itself does not consist of histones.

In summary, the correct statement among the given options is that the gene for producing insulin is not present in every body cell. Insulin is produced by specialized cells in the pancreas called beta cells, which contain the INS gene responsible for insulin production. Other cells in the body do not have this gene and do not produce insulin.