To review:
The sufficient and necessary stimulus required for ovulation in the female koala and possible cause of ovulation that could be removed through the experiment.
Introduction:
Most of the female mammals are spontaneous ovulators, meaning they release eggs in a cyclical fashion without an external stimulus. On the other hand, some of the female mammals like camels, koalas, and rabbits are reflex ovulators and require external stimulus to release their eggs. After postovulatory luteal phase, the levels of progesterone hormone increase; hence, in the given experiment, its levels have been measured in each of the groups.
It is already given as follows:
Experiment: The following four groups, each including nine female koalas were formed.
Group A: Artificial insemination of females with 1 milliliter (mL) of 0.9% sterile saline.
Group B: Artificial insemination of females with 1 mL of koala’s semen.
Group C: Urogenital sinus of females was artificially simulated with a glass rod.
Group D: Same treatment as in group C, which was followed by artificial insemination of females with 1 mL of koala’s semen.
After the above treatments, the progesterone levels were measured on 14 and 28 days from the blood samples. The mean standard deviations have also been shown in the following graph:
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