For those who don't get it, OP image shows the typical animated cum shot misconception that the ejaculate is pushed directly into the uterus, forcing its way through the cervix. This does not happen the way it's shown. The ejaculate is deposited just outside of the cervix, and the only the sperm swim through the cervix. It's important to understand this because some might come to the wrong conclusion that if they don't cum at full insertion, then the woman won't get pregnant. Not true. Sperm cells can swim the entire length of the vagina, and up through the cervix.

The ejaculate, everything that comes out, is not all semen. Semen makes up a small part of the ejaculate. Sperm are not semen, sperm are individual cells that make up, by volume, a tiny amount of the semen. A typical ejaculation contains about 100 million microscopic sperm cells.

In very rare instances, some ejaculate might enter the uterus through the cervix. But, one of the purposes of the cervix is to separate the sperm from the ejaculate.