In order of study blood circulation in rat, capillaries are observe in

Options

A. Mesentery
B. Kidney to liver
C. Liver
D. Lung

Answer

To answer the question regarding where capillaries are observed in the study of blood circulation in rats, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Blood Circulation**: Blood circulation in mammals, including rats, involves a network of blood vessels: arteries, veins, and capillaries.

2. **Identifying Capillaries**: Capillaries are the smallest blood vessels where the exchange of gases, nutrients, and waste occurs between blood and tissues.

3. **Role of Metarterioles**: Metarterioles are small blood vessels that connect arterioles to capillaries. They play a crucial role in regulating blood flow into the capillary beds.

4. **Location of Capillaries**: Capillaries are primarily found in tissues where they facilitate the exchange of materials. They are present in various organs and systems throughout the body.

5. **Conclusion**: In the context of the question, the capillaries are observed in the microcirculation system, specifically connected to the metarterioles, which link arteries to capillary networks.

### Final Answer:
Capillaries are observed in the microcirculation system, specifically in association with metarterioles.

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