怀孕的肥尾 (Sminthopsis crassicaudata) 的动态子宫内膜结构

During fertilization, an egg and sperm cell fuse to create a new diploid structure. In humans, the process occurs once the egg has been released from the ovary, and travels into the fallopian tubes. The process requires several key steps: 1) sperm present in the genital tract must locate the egg; 2) once there, sperm need to release enzymes to help them burrow through the protective zona pellucida of the egg; and 3) the membranes of a single sperm cell and egg must fuse, with the sperm...

The uterus, commonly called the womb, is a vital reproductive organ in females designed to provide a nurturing environment for the implantation and growth of an embryo. It is shaped like a hollow pear and positioned between the urinary bladder and the rectum. The uterus's structure allows it to support and protect a developing fetus throughout pregnancy.
The uterus is securely anchored within the pelvic cavity by paired broad ligaments on either side. It is further stabilized by three pairs of...

The uterine wall consists of three histological layers: the perimetrium, myometrium, and endometrium. The outermost perimetrium is a thin, serous membrane connected with the broad ligament on the sides, which helps anchor the uterus in the pelvic cavity. The thickest layer, myometrium, is mainly made up of smooth muscle tissue bundles. Its contractions are vital in facilitating the expulsion of the uterine lining, fetus, and placenta during menstruation and childbirth.
The endometrium is the...