The correct answers are
a. vaginal ring and
c. oral contraceptives.The vaginal ring is a soft, plastic ring that releases a continuous dose of the hormones oestrogen and progestogen into the bloodstream and prevents pregnancy. Oral contraceptives are also drugs for preventing pregnacy and also contain combinations of the hormones estrogen and progestin )or progestin alone=. Estrogen and progestin inhibit the release of the hormones luteinizing hormone (LH) and follicle stimulating hormone (FSH) which have a role in the ovulation.
Answer:
The alpha helices in the beta subunit are a ring shaped protein.
Explanation:
<em>Because the beta encircles DNA like a ring used gel filtration and radioactive beta subunit. Tipically beta and gamma complex are needed for fast and processive synthesis by polymerase III core. Some researchers realized that adding polymerase III core to the gel filtered isolated ³H-beta- DNA provide fast DNA synthesis typical of the polymerase III holoenzyme. Therefore the gamma complex is only needed to get the beta subunit onto the DNA, and is not required afterward.</em>