Topic: Development of heart and gut.
Question: Describe the developmental causes of primum and secondum type defects? “
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Atrioventricular septal defects (AVSDs) are congenital heart defects that involve abnormalities in the atrial and ventricular septa, as well as the atrioventricular (AV) valves. AVSDs are classified into two main types: primum and secundum defects. The developmental causes of primum and secundum type defects are distinct and involve different embryological processes.
- Primum type defects:
Primum type defects, also known as partial AV canal defects, are characterized by a deficiency in the inferior part of the atrial septum, the inlet portion of the ventricular septum, and the AV valve apparatus. This results in a large communication between the atria and ventricles and a single common AV valve instead of separate mitral and tricuspid valves.
The developmental cause of primum type defects is related to the abnormal formation of the endocardial cushions during embryonic development. The endocardial cushions are swellings of tissue that eventually fuse to form the atrial and ventricular septa and the AV valves. In primum type defects, there is inadequate fusion of the inferior and superior endocardial cushions, which leads to a persistent ostium primum (a defect in the atrial septum) and a deficient AV valve apparatus.
Genetic factors also play a role in the development of primum type defects. Primum type defects are commonly associated with Down syndrome (trisomy 21), which is caused by an extra copy of chromosome 21. Other genetic syndromes, such as heterotaxy syndrome and Noonan syndrome, can also be associated with primum type defects.
- Secundum type defects:
Secundum type defects, also known as ostium secundum defects, are the most common type of atrial septal defect (ASD). They are characterized by a deficiency in the central part of the atrial septum, resulting in a communication between the atria.
The developmental cause of secundum type defects is related to the abnormal formation or resorption of the septum primum and septum secundum, which are two structures that contribute to the formation of the atrial septum during embryonic development. The septum primum and septum secundum grow towards each other and eventually fuse to form the atrial septum. In secundum type defects, there is inadequate growth or excessive resorption of the septum primum, which leads to a deficiency in the central part of the atrial septum.
Genetic factors may also contribute to the development of secundum type defects. Secundum type defects can be associated with various genetic syndromes, such as Marfan syndrome, Holt-Oram syndrome, and Ellis-van Creveld syndrome. However, in most cases, secundum type defects occur sporadically without a clear genetic cause.
In summary, the developmental causes of primum and secundum type defects are distinct and involve different embryological processes. Primum type defects are related to the abnormal formation of the endocardial cushions and are commonly associated with genetic syndromes, such as Down syndrome. Secundum type defects are related to the abnormal formation or resorption of the septum primum and septum secundum and can be associated with various genetic syndromes, but often occur sporadically without a clear genetic cause.
Medicivils Medical Science Optional Test Series: Better Than UPSC Medico? Introduction The UPSC Civil Services Examination (CSE) is one of the most competitive exams in the world. The Medical Science optional is a popular choice for many candidates, as it covers a wide range of topics that are relevant to the UPSC syllabus. There are many different test series available for the Medical Science optional, but one of the most popular is the Medicivils test series. Medicivils is a coaching institute that specializes in the Medical Science optional, and their test series is known for its high quality and comprehensive coverage of the syllabus. In this article, we will compare the Medicivils Medical Science Optional Test Series to the UPSC Medico Test Series, and discuss why Medicivils is the better choice for UPSC CSE aspirants. Quality of Questions The quality of the questions in the Medicivils test series is very high. The questions are well-drafted and cover a wide range of topics from the syllabus. The questions are also challenging enough to test the candidates’ knowledge and understanding of the subject. The UPSC Medico test series, on the other hand, has been criticized for the quality of its questions. Some candidates have complained that the questions are too repetitive and do not adequately cover the syllabus. Comprehensiveness The Medicivils test series covers the entire Medical Science syllabus in great detail. The test series includes full-length tests, subject-wise tests, and topic-wise tests. This ensures that the candidates are thoroughly prepared for all aspects of the exam. The UPSC Medico test series, on the other hand, is not as comprehensive. The test series does not cover all of the topics in the syllabus in equal detail. Additionally, the test series does not include any topic-wise tests. Model Answer Sheets The Medicivils test series provides high-quality model answer sheets for all of its tests. The model answer sheets are written by experienced faculty members and provide detailed explanations for all of the questions. The UPSC Medico test series, on the other hand, does not provide model answer sheets for all of its tests. Even for the tests that do have model answer sheets, the quality is often not up to par. Personal Mentorship Medicivils offers personal mentorship to all of its students. The students can get their papers evaluated by experienced faculty members and receive personalized feedback. This helps the students to identify their strengths and weaknesses and to improve their performance. The UPSC Medico test series does not offer personal mentorship to its students. The students do not have the opportunity to get their papers evaluated by experienced faculty members and receive personalized feedback. Video Solutions Medicivils provides video solutions for all of its subject-wise tests. The video solutions are taught by experienced faculty members and provide detailed explanations for all of the questions. The UPSC Medico test series does not provide video solutions for its tests. Evaluation Medicivils evaluates the students’ papers within 7 days. The students’ papers are evaluated by experienced faculty members and they receive a detailed evaluation report. The UPSC Medico test series takes longer to evaluate the students’ papers. The students often have to wait for 10-15 days to receive their evaluation reports. Conclusion Overall, the Medicivils Medical Science Optional Test Series is the better choice for UPSC CSE aspirants. The Medicivils test series offers high-quality questions, comprehensive coverage of the syllabus, model answer sheets, personal mentorship, video solutions, and prompt evaluation. The UPSC Medico test series, on the other hand, has been criticized for the quality of its questions, lack of comprehensive coverage of the syllabus, lack of model answer sheets, lack of personal mentorship, lack of video solutions, and delayed evaluation. If you are serious about cracking the UPSC CSE with the Medical Science optional, then the Medicivils Medical Science Optional Test Series is the best choice for you.
