Explain why, a human zygote is more likely to grow into an adult than a frog zygote.

Answer

**Step-by-Step Solution:**

1. **Understanding Zygote Development**: A zygote is the initial cell formed when a sperm fertilizes an egg. The development of a zygote into an adult organism depends on various factors, including the environment in which it grows.

2. **Internal vs. External Development**: In humans, the zygote develops internally within the mother's womb. This internal environment provides a safe and controlled setting for the zygote to grow and develop into a fetus. It allows for the provision of nutrients, protection from external threats, and a stable temperature.

3. **Protection in Human Development**: The womb offers significant protection to the developing zygote. It shields the zygote from predators, environmental hazards, and fluctuations in temperature. This protection increases the chances of survival and successful development into an adult.

4. **Frog Zygote Development**: In contrast, frog zygotes develop externally. Frogs lay their eggs in water, where they are exposed to various environmental conditions and potential threats. This external development makes the eggs vulnerable to predators, such as fish and birds, which can significantly reduce their numbers.

5. **Survival Rate**: Due to the protective environment provided by the womb, human zygotes have a higher survival rate and are more likely to grow into adults compared to frog zygotes, which face numerous challenges and threats in their external environment.

6. **Conclusion**: Therefore, the primary reason a human zygote is more likely to grow into an adult than a frog zygote is the internal development in a protected environment for humans, as opposed to the external development of frogs, which is fraught with risks.

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