Pedígree for cystic fibrosis

Which of the following is a true statements about viruses? viruses have no nucleus. viruses are alive. viruses have a cell membrane. all viruses are deadly.

¿cómo demostraron los experimentos de griffith que un factor hereditario estaba involucrado en la transformación bacteriana?

Many birth-control pills release a constant amount of synthetic estradiols and progesterone for 21 days, followed by 7 days when no hormones are ingested. which of the following statements most accurately describes the effects of birth-control pills? -birth-control pills maintain constant levels of estrogens and/or progesterone so there is no surge in lh and ovulation does not occur.-birth-control pills inhibit the development of the uterine lining so implantation of a fertilized oocyte cannot occur.-birth-control pills maintain constant levels of estrogens and/or progesterones and mask the release of the oocyte from the follicle.-the 7 days with no hormones does not allow a thick enough uterine lining to form so a fertilized oocyte cannot implant.