This is the fallopian tube only a fraction of per have made it here and this will be there final test before fertilization: finding an egg. The eggs cecrete chemicals making it easy for spurm to find them and attach themselves to the egg.
this is the first stage that the sperm will go through, the vagina. Here, about 100 million to 1.6 billion enter through the vagina in a single ejaculation. Almost all of the sper die here after only 30 minutes due to acids created to protect the vagina
Here is the cervix. A small doorway after the vagina that is regularly clogged shut by mucus but during ovulation, estrogen hormones signal to loosen the mucus to make it easy for sperm to navigate through. Only about 60,000 sperm are still alive
The zygot then heads out off the fallopian tube and to the uterus. From there, the zygot attaches itself to the uterus lining and begins to multiply. After this, the zygot becomes an embryo
This is the uterus. Only 3000 sperm remain at this point and all of them try to navigate to the fallopian tube. the uterus expands and contracts to help navigate around. they need to do this all while fighting off white blood cells
Once attached to th egg cell the sperm ruleses its DNA into the egg and at that instant of fertilization the baby sex and appearance are set in stone. Once the egg has been fertilized it is called a zygote