How do mice get pregnant?

Mice, like many mammals, reproduce sexually. Here's a simplified breakdown of how they get pregnant:

1. Mating: Male mice have a penis that they use to deposit sperm into the female mouse's vagina.

2. Fertilization: The sperm travels through the female's reproductive tract and fertilizes an egg in the fallopian tubes.

3. Implantation: The fertilized egg, now called a zygote, travels down the fallopian tube and implants itself in the wall of the uterus.

4. Gestation: The embryo grows and develops inside the uterus for a gestation period of about 19-21 days.

5. Birth: After the gestation period, the mother mouse gives birth to a litter of pups.

Here are some additional details:

* Ovulation: Female mice release an egg, called ovulation, around every 4-5 days. They are most fertile during this period.

* Sperm: Male mice can produce millions of sperm cells, which can live for up to 24 hours inside the female's reproductive tract.

* Litter size: Mice can have litters of 4 to 12 pups.

* Multiple pregnancies: Mice can become pregnant again very quickly after giving birth, even within a few days.

It's important to remember that while this is a basic explanation, the process of pregnancy is complex and involves a variety of hormones and physiological processes.