Effects of Progesterone on the Uterine Lining. Progesterone plays an important part in the menstrual cycle. The menstrual cycle follows a precise pattern governed by the release of different hormones that interact with one another. Progesterone, whose production increases in the second half of the menstrual cycle, plays a pivotal part in preparing the uterine lining for implantation of an embryo. The corpus luteum, the remains of the ovulating follicle, produces progesterone after ovulation.
The pulmonary artery is the vessel transporting de-oxygenated blood from the right ventricle to the lungs. A common misconception is that all arteries carry oxygen-rich blood. It is more appropriate to classify arteries as vessels carrying blood away from the heart.
The aortic valve separates the left ventricle from the aorta, while the pulmonary valve separates the right ventricle from the pulmonary artery. As the ventricles contract, ventricular pressure exceeds arterial pressure, the semilunar valves open and blood is pumped into the major arteries.rom the right ventricle, blood flows through the pulmonary valve to the lungs via the pulmonary arteries (deoxygenated blood). In the lungs the blood becomes more red in color as it is oxygenated. Blood returns to the heart via the pulmonary veins (oxygenated blood) to the left atrium.