7. A bioengineer is trying to understand the biomechanics of a hole created in the skin for a transcutaneous implant. The engineer made a hole using a circular biopsy drill in the dorsal skin of a dog. The diameter of the drill is 5 mm. If the hole becomes an ellipse with a minor and major axis of 3 and 7 mm, answer the following questions. a. In which direction is the internal stress in the skin greater? b. In which direction are the collagen fibers more oriented? c. How can the bioengineer obtain a circular rather than an elliptical hole for the implant? d. Assuming the implant is non-deformable compared to the skin, what problems will arise between skin and implant when a load or force is applied to the skin or implant by handling accidentally?
