Morula is a stage of:
A. 1-32 cell
B. 20 cell
C. 24 cell
D. 16 cell
Correct Answer: D. 16 cell
Explanation
Morula is a stage of early embryonic development (cleavage stage).
Explanation:
After fertilization, the zygote undergoes a series of rapid mitotic divisions called cleavage. These divisions increase the number of cells without increasing the overall size.
- When the embryo reaches about 16–32 cells, it forms a solid ball of cells.
- This solid mass of blastomeres resembles a mulberry, hence the name morula (Latin morula = mulberry).
Key points:
- Stage: Cleavage stage of embryonic development
- Cell number: Usually 16 cells (may range up to 32 cells)
- Time: Around 3–4 days after fertilization
- Location: Fallopian tube / entering uterine cavity
- Next stage: Blastocyst
Conclusion:
👉 Morula is a stage of early embryonic development (cleavage stage), characterized by a solid ball of about 16 cells.
Other Options Details
Morula is a stage of early embryonic development, formed after repeated cleavage of the zygote.
Explanation of all options:
A. 1–32 cell
- This option describes the cleavage stage as a whole, ranging from 2-cell up to about 32-cell stage.
- Morula specifically appears at the upper end of this range, but the option is too broad.
- ❌ Not the best answer.
B. 20 cell
- Around 16–32 cells, the embryo becomes a solid ball of cells.
- A 20-cell embryo can be considered an early morula, but it is not the classical definition.
- ⚠️ Partially correct, but not standard.
C. 24 cell
- A 24-cell stage falls well within the morula stage.
- However, textbooks usually describe morula by a range, not a single number.
- ⚠️ Acceptable but not the most accurate.
D. 16 cell ✅ Correct answer
- Morula is classically defined as the 16-cell stage of the embryo.
- It looks like a mulberry (Latin: morula) and forms about 3–4 days after fertilization.
- ✔️ Best and most accepted answer.
Conclusion:
👉 Morula is a stage of the 16-cell embryo.
I hope that you liked this article.
Thanks!! 🙏 😊
Writer: Vandita Singh, Lucknow (GS India Nursing Group