Which of the following have macrolecithal eggs ?

Options

A. Aves, Reptilia
B. Aves, Reptilia, Amphibia
C. Aves, Reptilia, Chiroptera
D. Aves, Eutheria

Answer

To determine which of the following groups have macrolecithal eggs, we need to understand the classification of eggs based on the amount of yolk they contain. Here’s a step-by-step solution:

### Step 1: Understand the Types of Eggs
- **Alicythal Eggs**: These eggs have no yolk. Example: Human beings.
- **Microlecithal Eggs**: These eggs contain a very small amount of yolk. Example: Sea urchins and starfish.
- **Mesolecithal Eggs**: These eggs contain a moderate amount of yolk. Example: Frogs.
- **Macrolecithal Eggs**: These eggs contain a large amount of yolk. Examples: Birds (Aves) and reptiles (Reptilia).

### Step 2: Identify the Groups in the Question
The options provided in the question include:
1. Aves and Reptilia
2. Aves, Reptilia, and Amphibia
3. Aves, Reptilia, Chiroptera
4. Aves and Eutheria

### Step 3: Analyze Each Option
- **Option 1: Aves and Reptilia**: Both groups have macrolecithal eggs.
- **Option 2: Aves, Reptilia, and Amphibia**: Aves and Reptilia have macrolecithal eggs, but Amphibia (frogs) have mesolecithal eggs.
- **Option 3: Aves, Reptilia, Chiroptera**: Aves and Reptilia have macrolecithal eggs, but Chiroptera (bats) have microlecithal eggs.
- **Option 4: Aves and Eutheria**: Aves have macrolecithal eggs, but Eutheria (placental mammals) have alicythal eggs.

### Step 4: Conclusion
The correct answer to the question "Which of the following have macrolecithal eggs?" is **Aves and Reptilia**.