Gross anatomy of heart, anterior view

Nine major morphological forms of human and animal viruses.

The four sequential stages of a four-stroke diesel engine cycle from air intake to exhaust.

Eight major cranial and facial sutures visible from an anterior perspective of the human skull.

The nine primary organelles and structural components of a typical eukaryotic plant cell.

The nine fundamental architectural components and structural features of a medieval Romanesque church.

The principal anatomical structures of the thyroid and parathyroid glands in posterior view.

The nine fundamental structural components of a modern passenger car unibody frame.

The nine essential structures of the human lungs and bronchial tree, from the trachea to the pulmonary lobes.

Six fundamental exterior and structural elements of Gothic cathedral architecture.