The development of a zygote into a baby involves pre-embryonic development for the first 2 weeks, followed by embryonic development for the next 6 weeks, and finally fetal development until the baby is born. When is the developing baby considered a fetus?
Select one:
a. When most major organ systems have formed; the neural system forms during the fetal stage
b. Once gastrulation is complete
c. When all major organ systems have formed
d. After the neural tube forms
6 years ago
Answered By Kacie-Marie M
It is considered a fetus at 10 weeks of the pregnancy, well after gastrulation, so we can eliminate b). The neural tube is well formed in the second month, and thus the second part of a) would make it false. Although the neural system doesn’t fully develop until the fetal stage, the neural system is formed or at least forming.
While the neural tube if formed at this point, I wouldn’t say that that is the only criteria for it to progress from embryo to fetus.
The reproductive organs are beginning to form even if they can’t be seen at this early stage, they aren’t as developed as some of the other systems but they are forming at this point. The neural systems are forming along with digestive and sensory organs. The heart is developing at week 5, and lungs at week 8. Therefore I would say all major organ systems have formed even if they aren’t quite fully developed or in their final form. The wording of the question leads to easy confusion which is what I think they were hoping would happen, so it is possible they are looking for a different answer depending on what definition you've used for formed- if they want fully formed or beginning to form..
6 years ago
Answered By Kacie-Marie M
It is considered a fetus at 10 weeks of the pregnancy, well after gastrulation, so we can eliminate b). The neural tube is well formed in the second month, and thus the second part of a) would make it false. Although the neural system doesn’t fully develop until the fetal stage, the neural system is formed or at least forming.
While the neural tube if formed at this point, I wouldn’t say that that is the only criteria for it to progress from embryo to fetus.
The reproductive organs are beginning to form even if they can’t be seen at this early stage, they aren’t as developed as some of the other systems but they are forming at this point. The neural systems are forming along with digestive and sensory organs. The heart is developing at week 5, and lungs at week 8. Therefore I would say all major organ systems have formed even if they aren’t quite fully developed or in their final form. The wording of the question leads to easy confusion which is what I think they were hoping would happen, so it is possible they are looking for a different answer depending on what definition you've used for formed- if they want fully formed or beginning to form..