Question

The left and right hemispheres usually separate during which weeks of development?

1) Weeks 1-2
2) Weeks 3-4
3) Weeks 5-6
4) Weeks 7-8

Answer 1

The separation of the left and right brain hemispheres occurs between weeks 5 and 8 of the embryonic stage, a period rich with developmental milestones including limb movement, facial structure formation, and brain development.

Step-by-step explanation:

The left and right hemispheres of the brain typically separate during the embryonic stage, specifically between weeks 5-8 of development. During this period, significant developmental milestones take place, including the start of uncontrolled fetal limb movements in the sixth week, development of fingers and toes through the process of apoptosis, more complex facial structure formation including nostrils and outer ears, and by week 7, the lenses of the eyes. By week 8, all major brain structures are in place, and ossification begins to replace cartilage in the embryonic skeleton.