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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Rib ossification center first appears in which rib ?
assistant
The correct answer is  Ans. is 'c' i.e., 6thEach rib (except for 11th& 12th) is ossified from four centres :-One primary centre-->for bodyThree epiphyseal (secondary )centres for :-HeadAicular pa of tubercleNon aicular pa of tubercleOssification begins near the angle toward the end of 2" month (around 8th week) of fetal life, and is seen first in 6th and 7th ribs.The epiphyses for the head and tubercle make their appearance between 16th and 20th years, and are united to the body about the 25th year.