The malarial parasites initially multiply within the liver cells and then attack the red blood cells (RBCs) resulting in their rupture. The rupture of RBCs is associated with release of

Options

A. A toxic substance, hypnotoxin (responsible for chill and high fever) recurring every 6-7 days.
B. A toxic substance, hypnotoxin (responsible for chill and high fever) recurring every 3-4 days.
C. A toxic substance, hemozoin (responsible for chill and high fever) recurring every 6-7 days.
D. A toxic substance, hemozoin (responsible for chill and high fever) recurring every 3 - 4 days.

Answer

To solve the question regarding the release associated with the rupture of red blood cells (RBCs) due to malarial parasites, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Life Cycle of Plasmodium**:
- Malarial parasites (Plasmodium) have a complex life cycle that involves two hosts: the female Anopheles mosquito and humans.
- In humans, the parasites first multiply in the liver cells before invading the red blood cells.

2. **Multiplication in Liver Cells**:
- After entering the human body through a mosquito bite, the sporozoites of Plasmodium travel to the liver.
- In the liver, they undergo asexual reproduction, leading to the formation of merozoites.

3. **Invasion of Red Blood Cells**:
- The merozoites are released into the bloodstream and invade red blood cells.
- Inside the RBCs, they continue to multiply asexually.

4. **Rupture of Red Blood Cells**:
- Once the parasites have multiplied sufficiently, they cause the RBCs to rupture.
- This rupture leads to the release of various substances into the bloodstream.

5. **Release of Hemozoin**:
- One of the key toxic substances released during the rupture of RBCs is **hemozoin**.
- Hemozoin is a byproduct of the digestion of hemoglobin by the Plasmodium parasites.

6. **Symptoms Associated with Hemozoin**:
- The release of hemozoin is associated with symptoms such as chills and fever.
- These symptoms typically recur every 3-4 days, which is characteristic of malaria.

7. **Selecting the Correct Option**:
- Based on the information, the correct answer to the question is that the rupture of RBCs is associated with the release of **hemozoin**, which is responsible for chills and fever recurring every 3-4 days.

### Final Answer:
The rupture of RBCs is associated with the release of **hemozoin**, which causes chills and fever recurring every 3-4 days.

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