Blood platelets are present in the blood of

Options

A. Fishes
B. Amphibians
C. Reptiles
D. Mammals

Answer

**Step-by-Step Text Solution:**

1. **Identify the Types of Blood Cells**: Blood consists of three main types of cells: erythrocytes (red blood cells), leukocytes (white blood cells), and platelets (thrombocytes).

2. **Understand the Nature of Platelets**: Platelets are cell fragments that play a crucial role in blood clotting. They are colorless and do not have a nucleus.

3. **Formation of Platelets**: Platelets are produced from large cells in the bone marrow known as megakaryocytes. These megakaryocytes release cytoplasmic fragments into the bloodstream, which become platelets as they age.

4. **Function of Platelets**: The primary function of platelets is to aid in the coagulation of blood, which is essential for stopping bleeding when injuries occur.

5. **Presence of Platelets in Different Animals**: The question asks about the presence of blood platelets in various groups of animals: fishes, amphibians, reptiles, and mammals.

6. **Conclusion**: Based on the information, platelets are specifically found in mammals. Therefore, the correct answer to the question is that blood platelets are present in the blood of mammals.

**Final Answer**: Blood platelets are present in the blood of mammals.

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