The embryonic period of a time of rapid organogenesis. By about what age are all organ systems recognizable?

• A. Week 5
• B. Week 6
• C. Week 7
• D. Week 8

Answer: (D)

Verified step by step guidance

1. Understand the term 'organogenesis': Organogenesis is the process during embryonic development where the internal organs and structures begin to form.
2. Recognize the timeline of the embryonic period: The embryonic period spans from fertilization up to the end of the 8th week of pregnancy.
3. Identify key developmental milestones: During this period, the major organs and structures of the body are formed, a process that is largely completed by the end of the 8th week.
4. Consider the options given: Week 5, Week 6, Week 7, and Week 8. Compare these with the timeline of organogenesis.
5. Conclude that by the end of Week 8, all organ systems are recognizable, as this marks the transition from the embryonic period to the fetal period, where growth and maturation of the organs occur.