The scrotum is the external sac containing the testes and associated structures. Its skin, connective tissues and muscular components support protection and temperature regulation. The tunica vaginalis is a deeper serous covering rather than another name for the entire scrotal wall.

The peritoneum is a serous membrane lining the abdominal-pelvic wall and covering many of its organs. Reflections form structures such as mesenteries and omenta. Being covered by peritoneum is different from lying freely inside its potential cavity.

An omentum is a specialized fold of peritoneum associated with the stomach and adjacent organs. The greater omentum forms a mobile apron-like structure; the lesser connects the stomach and proximal duodenal region with the liver. These folds carry vessels and fat and participate in the organization of abdominal spaces.

The spermatic cord is a bundle running through the inguinal canal to the testis. It contains the ductus deferens, vessels, nerves and associated coverings. Transport of sperm is only one function: the vascular and neural components also support the testicular organ.

The inguinal canal is an oblique passage through the lower anterior abdominal wall. It transmits the spermatic cord in male anatomy and the round ligament of the uterus in female anatomy. Its layered wall and openings explain an important route for an inguinal hernia.

A mucous membrane is an epithelial lining with underlying support along a passage communicating with the exterior, such as the digestive or respiratory tract. Different locations have different epithelial specializations. The category does not mean that every surface region secretes the same amount or composition of mucus.

Soft tissue broadly denotes the body's non-bony supporting and connecting tissues, such as muscle, fat, fascia, vessels and nerves, with usage varying by context. It is a practical anatomical category rather than one histological tissue type.

Reproductive anatomy concerns the organs, ducts and supporting structures involved in gamete production, delivery and support of developing offspring. Human gonads produce gametes and hormones, while other structures perform transport, secretion or gestational roles. Shared proximity to urinary structures does not make the two systems identical.^[ref]

The anal canal is the terminal part of the digestive tract between the rectum and the exterior. Its sphincters and anal cushions contribute to continence. The dentate line marks an important epithelial and developmental transition within the canal.

The respiratory system supplies the pathways and exchange surfaces for movement of respiratory gases. In humans, the trachea and branching airways conduct air to alveoli, while the respiratory diaphragm and other respiratory muscles change thoracic volume. Ventilation moves air; exchange with blood additionally requires an appropriate surface and circulation.

Forearm supination rotates the forearm so that the palm faces anteriorly in anatomical position. The radius and ulna become approximately parallel, reversing the crossing produced by pronation. Both the supinator muscle and biceps brachii can contribute, with their relative action depending on joint position and load.

A mesentery is a fold of peritoneum supporting an abdominal organ and carrying its vessels, nerves and lymphatic routes. The intestinal mesentery allows considerable movement while preserving an organized supply. It is therefore both a mechanical attachment and a pathway for communication with the body.

An anatomist investigates the structure and spatial organization of living bodies. Methods include dissection, imaging and histology; comparative work also asks how corresponding structures differ among organisms. Structural description becomes explanatory when it connects geometry to physiology and biological development.

The ear is the sensory apparatus associated with hearing and, in its inner-ear components, balance. The outer and middle ear transmit sound mechanically toward the inner ear, where specialized sensory biological cells transduce movement into neural signals. Sound transmission and vestibular sensing are related anatomically but are different functions.

The stylomastoid foramen is an opening in the temporal bone between the styloid and mastoid processes. The facial nerve exits the skull through it. Damage near the opening can therefore affect facial motor output after the nerve's earlier intratemporal course.

The petrotympanic fissure is a narrow opening in the temporal bone connecting the middle-ear region with the infratemporal region. The chorda tympani passes through it. This supplies a route by which a nerve associated with the facial nerve reaches structures outside the ear.

The infratemporal fossa is a deep space below the temporal region and medial to the mandibular ramus. It contains muscles, vessels and nerves associated with mastication, including parts of the pterygoid musculature. Its importance lies in the relations among these crowded structures rather than a visible external boundary.

The buccal mucosa is the mucous membrane lining the inside of the cheek. It provides a flexible epithelial surface exposed to friction during mastication. It should be distinguished from the cheek's underlying buccinator muscle and from the gingiva around the teeth.

The gingiva is the gum tissue surrounding the teeth and covering the supporting alveolar region. It contributes a protective interface around each tooth. Its attached portions differ mechanically from the more mobile buccal mucosa.

The radial groove is a groove on the posterior humerus associated with the course of the radial nerve and profunda brachii vessels. Their close relation to the bone helps explain why an injury of the humeral shaft can also disturb nerve function.