Question

So we learnt in bio about the gastrulation in the human embryo, and about how the blastocyst splits into the endoderm, ectoderm and mesoderm, while being strictly protected from external diseases and micro-organisms by virtue of the placenta and various fluids and membranes.

My question is simple. At which point to E. coli enter our intestines?

Answer 1

E. Coli is everywhere. While it is true that the womb is sterile, both the birth canal and the outside environment are not. The baby will either breathe in or swallow some of the bacteria and it will take up residence in the intestines.

Answer 2

I see. Thank you!

Answer 3

nice question @aditkarekatte