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, leading to the formation of a zygote. This zygote is the initial cell formed when a sperm fertilizes an egg.

2. **Cleavage Process**: After the zygote is formed, it undergoes a series of mitotic divisions known as cleavage. This process involves the zygote dividing into multiple smaller cells called blastomeres.

3. **Formation of Morula**: The cleavage continues, leading to the formation of a solid ball of cells known as the morula. This stage typically occurs when the zygote has divided into 8 to 16 cells.

4. **Transition to Blastocyst**: Following the morula stage, the cells continue to divide and eventually form a hollow structure known as the blastocyst. This occurs as the morula moves towards the uterus.

5. **Identifying the Correct Option**: The question asks for the stage of morula in relation to other developmental stages. Since the morula forms after the zygote and before the blastocyst, the correct answer is option A: "between the zygote and blastocyst."

**Final Answer**: The morula is a developmental stage between the zygote and blastocyst.

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