By day 12 of embryonic development, mesoderm begins to form through
A) embryolization.
B) gastrulation.
C) mitosis.
D) meiosis.
E) none of the above

Question

Quizplus · Accepted Answer

Mesoderm formation is one of the major events during gastrulation, which occurs on or around day 12 of embryonic development. Gastrulation is the process of germ layer formation, where the blastula (hollow ball of cells) transforms into a gastrula with three primary germ layers - ectoderm, mesoderm, and endoderm. Mesoderm is formed from the invagination of the epiblast cells, which move inwards to create a middle layer between the ectoderm and endoderm.

By Day 12 of Embryonic Development, Mesoderm Begins to Form