Things too small to be viewed by a light microscope can be viewed with an Electron Microscope
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Human chorionic gonadotropin (hCG) is secrete by the embryo early in pregnancy to keep the corpus luteum for dying. This positive feedback will maintain the corpus luteum, which secretes Progesterone and Estrogens throughout pregnancy, in order to keep the endometrium well to nourish the embryo/fetus.
Answer:
Option (1), (2) and (3).
Explanation:
DNA is the genetic material of all the living organisms present on earth. The DNA contains the nitrogenous bases, pentose sugar and the phosphate group. DNA strands runs in the opposite direction and shows polarity.
Watson and Crick explain the structure of DNA based on the X ray diffraction produced by Rosalind. According to the structure, chromosomes are present in the nucleus and contains the DNA and wrapped around the proteins. The genes is considered as the functional segment of DNA.
Thus, the correct answer is option (1), (2) and (3).
