histological bone, elastic cartilage human and joint of human foetus under the microscope for education.

uterus stage infant foetus development placenta fetus study organ myocardium bone plates microscope cell background microscopy smooth column arch canal contraction ornament epithelium elastic cartilage biopsy science micro structure abstract medicine connective nucleus health tubular biology fiber histological striated human muscle tissue skeleton histology osteopathy research scientific skeletal anatomy joint education