Write down the life cycle of Ankylastoma duodenale ?

Q. 16. Write down the life cycle of Ankylastoma duodenale ?
Life cycle of Ankylastoma duodenale :-  There are five stages of life cycle, These are:-
A. Stage 1 :- Passage of eggs from the infected host. The eggs are passed out in the feces of the human host.
B. Stage 2 :- Development in the soil. From each egg a rihabditiform larva hatches out in the soil in about 2 days. The rihabditiform larva moults twice on the 3rd and the 5th day.
The rihabditiform larva develops into a filariform larva it takes another 6 to 8 days. Filiriform larvae are infective to man.
C. Stage 3 :- Entrance into a new host. The filariform larvae penetrate human skin and reach in the subcutaneous tissue. This may give rise to a purity rash.
D. Stage 4 :- Migration through lungs. From subcutaneous tissue the larvae enter into the lymphatic or small venules. They pass through the lympho- vascular system into the venous circulation and carried to the lungs via right heart. After entering the alveoli they ascend the bronchi trachea and larynx, then craul over the epiglottis to the book of the pharynx and are ultimately swallowed. This migration takes about 10 days.
During migration or 0on entering the oesophagus a third moulting takes place.
E. Stage 5 :- Localization and laying of eggs. The growing larvae develops in the small intestine. Reaching maturity 4-7 weeks after infection. The fertilized females to lay eggs in the face. During maturation, a fourth moulting take place in the small intestine.