I'm pretty sure that the main purpose of the U.S. Bill of Rights is to define the civil liberties of American citizens. It refers to the first 10 amendments of the U.S. Constitution. Also, it was introduced in 1789 to guarantee the protection of the basic rights that citizens continue to enjoy.
A histone is a protein that interacts with DNA to coil it into a nucleosome.
A nucleosome is a small unit of DNA coiled around 8 histone proteins.
Therefore, the major difference is that a nucleosome is a small structure and histones are the proteins that help form the structure.
Answer:
Spermatozoa: 23 chromatids
Ootid: 23 chromatids
Anaphase of mitosis: 92 chromatids
Oogonium prior to S phase: 46 chromatids
Explanation:
1) Spermatozoa, also known as sperm cell is a haploid gamete (n) that results from the meiotic division of a dipoid reproductive cell. Since there are 23 pairs of chromosomes or 46 chromosomes in human somatic cells, there will be 23 chromosomes in the spermatozoa. Also, meiotic division occurs twice and separates sister chromatids in meiosis II. Hence, spermatozoa will contain 23 chromosomes (n) with 1 chromosome each i.e. 23 chromatids
2) Ootid is a haploid cell that arises from the second meiotic division of a secondary oocyte. A primary oocyte, with 46 chromosomes/92 chromatids, undergoes meiosis I to produce secondary oocyte with 23 chromosome/46 chromatids, which in turn undergoes meiosis II to produce ootid with 23 chromosomes/23 chromatids (each chromatid is an individual chromosome).
3) Mitosis is the cell division that produces two identical diploid (2n) daughter cells. Note that, 46 chromosomes get replicated to form 92 chromatids. In the anaphase stage of mitosis, sister chromatids get pulled apart to opposite poles but still remain in the cell as cytokinesis is yet to occur.
4) Oogonium is the diploid (2n) cell that gives rise to primary oocyte via mitosis. Prior to the S phase where chromosomes replication occurs, Oogonium cell will contain 46 chromosomes and 46 chromatids.
Answer: C
Explanation: This happens because RNA becomes double stranded when two self complementary region of a single strand form a hairpin like structure...
The correct answer is 1, tight junctions. Tight junctions are the junctions seal adjacent epithelial cells in a narrow band just beneath their apical surface. They contain a network of claudins and other proteins. They limit the passage of molecules and ions through the space between cells.
