Science has a darn sexist history. Possibly peaking with this diagram of a sperm by Hartsoeker ‪‬

This is one of the first scientific drawings of human sperm made by Nicolaas Hartsoeker a student of Antonie van Leeuwenhoek the father of microscopy. When Nicolaas looked down the microscope at human sperm (try not to think about where he got this), he saw a tiny almond shaped head with a long tail. Nicolaas believed that in this almond was infact a tiny little person he called homunculi which is latin for little man. After mating (scientists don’t say sex) this person would then be incubated by the women and slowly grow into a full size baby and eventually into an adult human. Essentially reducing the role of women in procreation into the oven within which the bun is baked. What we know now is that the mother’s DNA is split in two during the egg making process and the father’s DNA is split into two during the sperm making process, so when the sperm enters the egg the resulting embryo has 50% of it’s DNA from the mother and 50% from the father. But that isn’t strictly true. You see we actually have two separate sources of DNA, we have our normal DNA that is in our chromosomes and sits in the middle of the cell (in the nucleus) AND we have have mitochondrial DNA. The mitochondria is small little organelle that sits inside most cell types in the body. It is the power generator of our body and acts like a little battery pack using chemical energy from glucose to power each cell. These mitochondria have their own DNA and this DNA comes solely from your mother. Which means that you aren’t 50% your mother and 50% your father you are actually 50.00057% your mother and 49.99943% your father! Basically that is biology saying screw the patriarchy!