Grayscale illustration of a heart assist system, which provides a patient in heart failure with full circulatory assistance, allowing the heart to rest. The system is often used to assist patients in heart failure while they are waiting for a heart transplant.

Grayscale illustration of three cross section views of the human eye, showing normal anatomy (left), glaucoma (top right), and cataracts (bottom right). Glaucoma is caused by a buildup of fluid that increases pressure in the eyeball, damaging the optic nerve. A cataract is caused by changes in proteins that cause the lens to become opaque.

Grayscale illustration of a normal human heart, showing the atria, ventricles, and major blood vessels; cutaway cross section.

Grayscale illustration of a human cerebrum superimposed on a head silhouette, side view (top) and cross section (bottom). The side view shows the anterior convexity of the frontal lobe, Broca's area, and inferior parietal lobe. The cross section shows the hippocampus, uncus, anterior commissure, corpus callosum, and anterior portion of the gyrus cinguli.

Illustration of the male reproductive organs, frontal and cutaway views. Shown are the penis, internal spermatic artery, vas deferens, testis (covered by the visceral tunica vaginalis), and scrotum.

Grayscale illustration of a human head and neck, shown from the nose to the shoulder in cross section. Included are the nasal cavity, mouth, tongue, epiglottis, larynx, vocal cords, esophagus, and trachea (windpipe).

Black and white line drawing of a normal human foot, with an emphasis on the talus (heel) bone, side view.

Grayscale illustration of bottom of a normal human foot. Shown is the plantar fascia, a fibrous band of tissue on the sole of the foot that helps to support the arch. Plantar fasciitis is a painful condition caused by inflammation of the fascia.

Grayscale illustration of normal human scapula tendons and muscles, front (right) and back (left). Shown are the supraspinatus tendon and muscle, the subscapularis tendon and muscle, and the infraspinatus tendon and muscle.

Grayscale illustration of a normal human epiglottis (left) and a vocal abused epiglottis with callus like nodules (right). Shown are the root of the tongue and the vallecula (a crevice behind the root of the tongue between the folds of the throat).

Illustration of a human postmenopausal uterus (front and cutaway views). Shown are the vagina, cervix, uterus, fallopian tubes, fimbria, and ovaries.

Grayscale illustration of the normal muscles and tendons of a human lower right leg.

Grayscale illustration of a normal human kidney, cutaway cross section. Shown are the ureter, renal pelvis, major calyces, pyramids, cortex, and medulla.

Illustration of a normal human knee. Shown are the femur, medial capsular ligament, tibial collateral ligament, lateral capsular ligament, and tibia.

Grayscale illustration of common dental erosion. In the painless early stages of this disease, bacteria enter pockets between the teeth, causing progressive erosion. In advanced stages, with underlying bone and connective tissue destroyed, teeth may loosen and fall out.

Illustration of a normal human vertebral column (lateral view). Shown (from top to bottom) are the atlas (cervical vertebra 1: C1), axis (C2), cervical vertebrae 3-7 (C3-C7), thoracic vertebrae 1-12 (T1-T12), lumbar vertebrae 1-5 (L1-L5), sacrum (a group of 5 fused vertebrae), and coccyx.

Illustration of a normal human vertebra and its surroundings (top view). Shown are the vertebral body (left center), vertebral vein and artery (dark blue and red), spinal cord (in white, right center), spinal nerve root (yellow), and spinous process (far right center).

Illustration of the hip joint capsule ligaments, anterior view. Shown are the iliofemoral ligament (also known as the Y-shaped ligament of Bigelow) (above) and the pubofemoral ligament (below).

Illustration of the hip joint capsule ligaments, dorsal view. Shown are the iliofemoral ligament (above), ischiofemoral ligament (center), and the zona orbicularis (below).

Illustration of meniscus tears in the human knee. Shown are a longitudinal tear (top left) that may develop into a bucket handle tear (top right); a radial tear (center left) that may develop into a parrot beak tear (center right); and a horizontal tear (bottom left) that may develop into a flap tear (bottom right).