Zygote may be compared to

Options

A. Single celled ancestor of some animals
B. Prokaryotic ancestor of all organisms
C. Single celled ancestor of all animals
D. Colonial protozoan ancestor of metazoans

Answer

To solve the question "Zygote may be compared to," we need to analyze the options given and understand the characteristics of a zygote.

### Step-by-Step Solution:

1. **Understanding the Zygote**:
- A zygote is the initial cell formed when a sperm cell fertilizes an egg cell. It is a single-celled organism that represents the earliest stage of development in animals.

2. **Evaluating the Options**:
- **Option 1: Single-celled ancestor of some animals**:
- This option suggests that the zygote is only the ancestor of some animals. However, zygotes are present in all animals, not just some. Therefore, this option is incorrect.

- **Option 2: Prokaryotic ancestor of all organisms**:
- Prokaryotes are organisms that do not have a nucleus (like bacteria). Zygotes are eukaryotic (having a nucleus) and are not related to prokaryotic ancestors. Thus, this option is also incorrect.

- **Option 3: Single-celled ancestor of all animals**:
- This option states that the zygote is a single-celled ancestor of all animals. This is true because all animals develop from a zygote, which is a single cell that eventually divides and differentiates into all the various cell types in an organism.

- **Option 4: Colonial protozoa ancestor of Metazoans**:
- This option implies that the zygote is a colonial protozoan ancestor of Metazoans (multicellular animals). However, zygotes are not colonial; they are individual cells. Therefore, this option is also incorrect.

3. **Conclusion**:
- After evaluating all the options, the correct comparison for a zygote is **Option 3: Single-celled ancestor of all animals**.

### Final Answer:
Zygote may be compared to the **single-celled ancestor of all animals**.