Eggs of egg laying mammals are

Options

A. Macrolecithal
B. Alecithal
C. Mesolecithal
D. Telolecithal .

Answer

To answer the question "Eggs of egg-laying mammals are," we need to analyze the types of eggs based on the amount of yolk present. Here’s a step-by-step solution:

### Step 1: Understand the Types of Eggs
Eggs can be classified based on the amount of yolk they contain. The terms used to describe these classifications include:
- **Macrolecithal**: Eggs with a large amount of yolk.
- **Mesolecithal**: Eggs with a moderate amount of yolk.
- **Microlecithal**: Eggs with a very small amount of yolk.
- **Alcithal**: Eggs with no yolk.

### Step 2: Identify the Characteristics of Mammals
In general, most mammals have very little yolk in their eggs because they nourish their embryos through a placenta. This means that typical mammalian eggs are classified as **microlecithal** or **alecithal**.

### Step 3: Focus on Egg-Laying Mammals
However, egg-laying mammals (like the platypus) are different. They lay eggs that contain a significant amount of yolk, similar to the eggs of reptiles and birds. This is necessary to support the development of the embryo outside of the mother's body.

### Step 4: Classify the Eggs of Egg-Laying Mammals
Given that egg-laying mammals have eggs with a substantial amount of yolk, they are classified as **macrolecithal**. This classification indicates that their eggs have enough yolk to sustain the embryo during its early development.

### Conclusion
Thus, the correct answer to the question "Eggs of egg-laying mammals are" is **macrolecithal**.

### Final Answer
**Eggs of egg-laying mammals are macrolecithal.**

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