During an allergic reaction, histamine is released into blood by

Options

A. Eosinophils
B. Basophils
C. `I_gE`
D. Neutrophils

Answer

To solve the question "During an allergic reaction, histamine is released into blood by?", we can follow these steps:

### Step 1: Understand the context of allergic reactions
Allergic reactions are immune responses that occur when the body encounters a substance (allergen) that it mistakenly identifies as harmful.

**Hint:** Allergic reactions involve the immune system and specific cells that respond to allergens.

### Step 2: Identify the role of histamine
Histamine is a chemical that plays a crucial role in the immune response. It is involved in the inflammatory response and is responsible for many of the symptoms associated with allergies, such as itching, swelling, and redness.

**Hint:** Histamine is a key player in the symptoms of allergies.

### Step 3: Identify the cells involved in the release of histamine
The cells primarily responsible for the release of histamine during an allergic reaction are mast cells and basophils. These cells release histamine when they are activated by allergens.

**Hint:** Look for cells that are known to release histamine in response to allergens.

### Step 4: Analyze the options provided
The options given are:
1. Eosinophils
2. Basophils
3. Immunoglobulin E antibody
4. Neutrophils

Among these options, we need to identify which cell type is responsible for the direct release of histamine.

**Hint:** Focus on the immune cells that are known for their role in allergic reactions.

### Step 5: Determine the correct answer
- **Eosinophils** are primarily involved in combating parasitic infections and play a role in allergic responses but do not directly release histamine.
- **Basophils** are known to release histamine when activated, particularly in allergic reactions.
- **Immunoglobulin E (IgE)** is an antibody that binds to allergens and triggers the activation of mast cells and basophils but does not release histamine itself.
- **Neutrophils** are primarily involved in fighting bacterial infections and do not play a significant role in allergic reactions.

Based on this analysis, the correct answer is **Basophils**.

**Final Answer:** During an allergic reaction, histamine is released into the blood by **Basophils**.