Question

The route through which developmental stages of Ascaris serially pass in man is

• A. Outside $\to$ Intestine $\to$ Liver $\to$ Heart $\to$ Lung $\to$ Intestine $\to$ Outside
• B. Outside $\to$ Oesophagus $\to$ Stomach $\to$ Heart $\to$ Lung $\to$ Liver $\to$ Intestine $\to$ Outside
• C. Outside $\to$ Mouth $\to$ Intestine $\to$ Liver $\to$ Lung $\to$ Heart $\to$ Trachea $\to$ Outside
• D. Outside $\to$ Trachea $\to$ Lung $\to$ Heart $\to$ Liver $\to$ Intestine $\to$ Outside

Answer 1

The correct option is A Outside $\to$ Intestine $\to$ Liver $\to$ Heart $\to$ Lung $\to$ Intestine $\to$ Outside

The Ascaris is known to cause infection in the human being when the ingested fertilized eggs get converted to a larval worm, which easily enters the duodenum and then the blood stream. From there it goes to the liver through portal system, the heart followed by lungs through the circulatory system. The larva moults in the lungs and then passes to the small intestine to get converted into an adult worm and then final moves out of the body with feces. Thus, the correct answer is option A.