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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
The structural proteins are involved in maintaining the shape of a cell or in the formation of matrices in the body. The shape of these proteins is
assistant
The correct answer is  Collagen is the most abundant of the fibrous proteins that constitute more than 25% of the protein mass in the human body. Other prominent fibrous proteins include keratin and myosin. These fibrous proteins represent a primary source of structural strength for cells (i.e., the cytoskeleton) and tissues.Ref: Harper 28th Ed. Page-40, Harper 27th Ed. Page: 38