Speaking as someone who used to teach, "Basic Biology" is almost entirely convenient lies to tell children that get them ready to understand it properly in further education.
"Basic physics" is that planes attain lift because the air takes longer to go over the wing than under it.

Theres no one property that *is* "Biological Sex". Changing even one of the properties that make up the cluster is making concrete and real changes to your sex, and the act of transition makes profound changes to many of them. Trans men grow prostate tissue, women develop a hormonal cycle,

Video in question. Let's make it viral again.