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Introduction: Gastrointestinal tract also called the digestive tract formation starts in the third week of the pregnancy. This tract extends from the buccopharyngeal membrane to the cloacal membrane.
Answer to Problem 6TY
Correct answer: In vertebrates, the digestive tract forms from the archenteron. Hence, the correct answer is option c.
Explanation of Solution
Reason for correct answer:
Archenteron is also called the primitive gut and it develops from the vegetal plate which undergoes the process of primary invagination. After the primary invagination, the archenteron undergoes secondary invagination for the elongation. This elongation is responsible for extension of the gastrointestinal tract from the buccopharyngeal membrane to the cloacal membrane.
Option c. is given as “the archenteron.”
The digestive tract in vertebrates, forms from the archenteron. Hence, the correct answer is option c..
Reason for incorrect answer:
Option a. is given as “the blastopore.”
Blastopore is the site for the initiation of the gastrulation in an embryo. It does not form a complete digestive tract. Hence, option a. is incorrect.
Option b. is given as “the dorsal lip.”
The dorsal lip is responsible for the formation of notochords in vertebrates. Hence, option b. is incorrect.
Option d. is given as “the mesoderm”
The mesoderm is responsible for the development of organs in the body of the vertebrate, but it is not responsible for the digestive tract formation. Hence, option d. is incorrect.
Option e. is given as, “both a and d.”
The blastophore only forms the opening of the gastrulation tract and mesoderm forms the vital organs of the body. Hence, option e. is incorrect.
Hence, the options a., b., d. and e. are incorrect.
Archenteron give rise to digestive tract in vertebrates.
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