How Does Chromosomal Heredity Work 🌱

We are all made of 46 chromosomes

• 23 you get from your dad
• 23 from your mom
• They form pairs with each other

Your parents are each made up of 46 chromosomes

When your parents created you, recombination happens and random parts of your mom’s 1st chromosome pair for example are stitched together to make a single chromosome (same for your dad and this repeats for every chromosome pair)

I always thought of punnit squares as essentially deterministic basically but they aren’t

• basically if your mom is Rr then you will randomly inherit either an R or an r from her. If dad is RR then you can only inherit R from them so you will appear to have the dominant gene if people look at you, but you could either get RR or Rr since you don’t know what your mom gave you
• in recombination you can actually get entirely new gene traits that aren’t from either parent, like having a kid with type A blood even if both parents have type O or type B blood genes (not as simple as just taking specific genes from chromosomes, you are like literally cutting parts off and stitching other parts together)
• mutations can also cause new traits to evolve
• male semen determines sex by giving either a Y chromosome (male) or X chromosome (female), there is some recombination that occurs between X and Y chromosomes in the male but not as much as in the females X to X chromosomes