The midsagittal plane divides the human body into equal left and right halves. If divided along this plane, the deepest structures of the human body will be visible.
Starting with the most superior portion of the body, visible would be the brain. Cut long the midsagittal plane, the structures of the brain which would exposed include the pineal body, the corpus callosum, thalamus, midbrain, pons, medulla oblongata, hypothalamus, and the arbor vitae of the cerebellum.
Inferior to the brain would be the brain stem. Also, one would see the inside of the larynx and trachea and esophagus. The middle of the thyroid and thalamus would also be visible.
Within the thoracic cavity, the midsaggital plane intersects the heart which is housed in the mediastinum of the thoracic cavity.
Once below the diaphragm, visible would be an internal view of the liver, stomach, pancreas, small intestine, a cross section of the transverse colon and rectum, the bladder, and an inside view of the urethra. In the female body the plane would intersect the uterus and vagina, while in the male body it would intersect the opening of the prostate where the urethra passes through.