Morula is a developmental stage

Options

A. between the zygote and blastocyst
B. between the blastocyst and gastrula
C. after the implantation
D. between implantation and parturition

Answer

### Step-by-Step Solution:

1. **Understanding the Developmental Stages**: The human reproductive process begins with fertilization, resulting in the formation of a zygote. This zygote undergoes several developmental stages.

2. **Formation of Zygote**: After fertilization, the zygote is formed. This is the initial single-cell stage of development.

3. **Cleavage**: The zygote undergoes a series of mitotic divisions known as cleavage. During this process, the zygote divides into multiple smaller cells without increasing in size.

4. **Blastomeres Formation**: As a result of cleavage, the zygote produces daughter cells called blastomeres. The number of blastomeres increases exponentially (2, 4, 8, 16, etc.).

5. **Morula Stage**: When the zygote reaches approximately 8 to 16 blastomeres, it is referred to as the morula. This stage occurs while the developing embryo is still moving towards the uterus.

6. **Transition to Blastocyst**: After the morula stage, further divisions and differentiation occur, leading to the formation of the blastocyst, which is the next stage of development.

7. **Conclusion**: Therefore, the morula is a developmental stage that occurs between the zygote and the blastocyst.

### Final Answer:
Morula is a developmental stage between Zygote and Blastocyst.

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