In human and zoological anatomy (sometimes called zootomy), several terms are used to describe the location of organs and other structures in the body of bilateral animals. These terms are listed and explained here. In some cases, the terminology in human anatomy may differ from that in general anatomy.
The anatomical position holds more relevant information on relations and terms of location for human anatomy. Anatomical drawing of the human muscles from the Encyclopédie. ... Zootomy is the zoological discipline that focuses on animal anatomy, in particular on the dissection of animals. ... In biology, an organ (Latin organum: instrument, tool) is a group of tissues, which perform a specific function or group of functions. ... Superphyla Protostomia Deuterostomia The Bilateria is a branch of Metazoa. ... Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria Placozoa Subregnum Bilateria  Acoelomorpha  Orthonectida  Rhombozoa  Myxozoa  Superphylum Deuterostomia     Chordata (vertebrates, etc. ... Human anatomy or anthropotomy is a special field within anatomy. ... The anatomical planes The anatomical position is a schematic convention for describing the relative morphology of the human body. ...

Directions

Anatomical directions and planes shown on a kangaroo.

Anatomical directions and planes shown on a kangaroo. ... Anatomical directions and planes shown on a kangaroo. ...

General usage

Animals typically have one end with a head and mouth, with the opposite end often having the anus and tail. The head end is the cranial end; the tail end is the caudal end. Within the head itself, rostral refers to the direction toward the end of the nose, and caudal is still used to refer to the tail direction. In zootomy, several terms are used to describe the location of organs and other structures in the body of bilateral animals. ... In zootomy, several terms are used to describe the location of organs and other structures in the body of bilateral animals. ... In zootomy, several terms are used to describe the location of organs and other structures in the body of bilateral animals. ...

The surface or side of the body normally oriented upwards, away from the pull of gravity, is the dorsal side; the opposite side, typically the one closest to the ground when walking on all legs, swimming or flying, is the ventral side. For example: in vertebrates, the spine or nerve chord is located on the dorsal side of the organism. A cow's udder is on the ventral side. A dolphin's dorsal fin is, unsurprisingly, on the dorsal side. Typical classes Petromyzontidae (lampreys) Placodermi - extinct Chondrichthyes (cartilaginous fish) Acanthodii - extinct Actinopterygii (ray-finned fish) Actinistia (coelacanths) Dipnoi (lungfish) Amphibia (amphibians) Reptilia (reptiles) Aves (birds) Mammalia (mammals) Vertebrata is a subphylum of chordates, specifically, those with backbones or spinal columns. ... The vertebral column seen from the side The vertebral column (backbone or spine) is a column of vertebrae situated in the dorsal aspect of the abdomen. ...

On the limbs or other appendages, a point closer to the main body is "proximal"; a point farther away is "distal".

The right and left side (sometimes in Latin: dexter - right, and sinister - left) are given as viewed from the animal that is described. Ipsilateral means on the same side, while contralateral means on the other side. Latin is the language originally spoken in the region around Rome called Latium. ...

Usage in human anatomy

In human anatomy, the body and its parts are always described using the assumption that the body is in anatomical position (main article), i.e. standing upright. The anatomical planes The anatomical position is a schematic convention for describing the relative morphology of the human body. ...

Portions of the body which are closer to the head end are "superior" ("upper"); those which are farther away are "inferior" ("lower") -- superior corresponds to cranial, and inferior to caudal. Objects near the front are "anterior"; those near the rear are "posterior" -- these correspond respectively to "ventral" and "dorsal".

The terms "anterior" and "posterior" should not be used when referring to most animals however, and are particularly incorrect for quadrupeds. In this case, rostral/cranial and caudal are more appropriate. A quadruped is an animal having exactly four walking legs. ...

Please visit the anatomical position page for more information for terminology for human anatomy. The anatomical planes The anatomical position is a schematic convention for describing the relative morphology of the human body. ...

Relative directions

Structures near the midline are called medial and those near the sides of animals are called lateral. Therefore, medial structures are closer to the midsagittal plane, lateral structures are further from the midsagittal plane. Structures in the midline of the body are median. For example, your cheeks are lateral to your nose and the tip of the nose is in the median line.

Structures that are close to the center of the body are proximal or central, while ones far removed are distal or peripheral. For example, the hands are at the distal end of the arms, while the shoulders are at the proximal ends. These terms can also be used relatively to organs, for example the proximal end of the urethra is attached to the bladder. Male anatomy Female anatomy In anatomy, the urethra is a tube which connects the urinary bladder to the outside of the body. ... The interior of bladder. ...

Structures on or closer to the body´s surface are superficial (or external) and those further inside are profound or deep (or internal).

When speaking of inner organs, visceral means close to or attached to the organ, while parietal is more distant. For example, the visceral pleura is attached to the lung and the parietal pleura is attached to the chest wall. In anatomy, the pleural cavity is the potential space between the lungs and the chest wall. ...

Relative directions in the limbs

In the limbs of most animals, the terms cranial and caudal are used in the regions proximal to the carpus (the wrist, in the forelimb) and the tarsus (the ankle in the hindlimb). Objects and surfaces closer to or facing towards the head are cranial; those facing away or further from the head are caudal. This usage is not common in human antomy, however. In human anatomy, the wrist is the flexible and narrower connection between the forearm and the hand. ... The bones in the foot In anatomy, the ankle is the part of the lower limb that is located between the foot and the leg. ...

Distal to the carpal joint, the term dorsal replaces cranial and palmar replaces caudal. Similarly, distal to the tarsal joint the term dorsal replaces cranial and plantar replaces caudal. For example, the top of a dog's paw is its dorsal surface; the underside, either the palmar (on the forelimb) or the plantar (on the hindlimb) surface. Trinomial name Canis lupus familiaris (Linnaeus, 1758) The Dog is a canine carnivorous mammal that has been domesticated for at least 14,000 years and perhaps for as long as 150,000 years based on recent evidence. ... A paw is the soft foot of an animal. ...

The sides of the forearm are named after its bones: Structures closer to the radius are radial, and structures closer to the ulna are ulnar. Similarly, in the lower leg, structures near the tibia (shinbone) are tibial and structures near the fibula are fibular (or peroneal). The radius and ulna of the left forearm, posterior surface. ... The ulna (along with the radius) is one of the two bones in the forearm. ... In human anatomy, the tibia (Shin Bone) is the larger of the two bones in the leg below the knee. ... The fibula (Calf Bone) is a bone placed on the lateral side of the tibia, with which it is connected above and below. ...

Planes

General usage

Three basic reference planes are used in zoological anatomy. The sagittal plane divides the body into left and right portions. A coronal plane divides the body into dorsal and ventral portions. A transverse plane divides the body into cranial and caudal portions.

Usage in human anatomy

Sometimes the orientation of certain planes need to be distinguished, for instance in medical imaging techniques such as CT scans, MRI scans or PET scans. One imagines a human in anatomical position (standing, arms hanging down with palms to the front) and an X-Y-Z coordinate system with the X-Y plane parallel to the ground, the X-axis going front and back, the Y-axis passing left and right, and the Z-axis going up and down. Medical imaging is the process by which physicians evaluate an area of the subjects body that is not normally visible. ... CT apparatus in a hospital Computed axial tomography (CAT), computer-assisted tomography, computed tomography, CT, or body section roentgenography is the process of using digital processing to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around... 3D rendered MRI Magnetic resonance imaging (MRI) - also called magnetic resonance tomography (MRT) - is a method of creating images of the inside of opaque organs in living organisms as well as detecting the amount of bound water in geological structures. ... Positron emission tomography (PET) is a nuclear medicine medical imaging technique which produces a three dimensional image or map of functional processes in the body. ... The anatomical planes The anatomical position is a schematic convention for describing the relative morphology of the human body. ... Cartesian means relating to the French mathematician and philosopher Descartes, who, among other things, worked to merge algebra and Euclidean geometry. ...

• A transverse or axial plane is an X-Y plane, parallel to the ground, which (in humans) separates the superior from the inferior, or put another way, the head from the feet.
• A coronal or frontal plane is an Y-Z plane, perpendicular to the ground, which (in humans) separates the anterior from the posterior, the front from the back, the ventral from the dorsal.
• A sagittal plane is a X-Z plane, perpendicular to the ground and to the coronal plane, which separates left from right. The midsagittal plane is the specific sagittal plane that is exactly in the middle of the body.

Relative motions

Flexion means approximating adjacent parts of the body (usually at a joint) and extension means separating them. For example, the legs are flexed at the knee joints when sitting down, and extended when standing up. Generally, flexion produces an acute angle between adjacent parts, with its vertex at the joint, and extension produces an obtuse angle. One exception to this rule is in the ankle joint where moving the foot such that the toes move upwards is dorsiflexion and moving the foot such that the toes move downwards is plantar flexion. This article is about angles in geometry. ...

Adduction means moving a part of the body toward or past its median line or toward the long axis of a limb. Abduction means moving a part of the body away from its median line or away from the long axis of a limb. For example, adducting the thighs brings the legs together, and abducting the thighs spreads the legs apart. Similarly, adducting the fingers or vocal folds brings them into contact with one another, and abducting the fingers or vocal folds spreads them apart.

Rotation means moving a part about its long axis, for example, in turning the neck. Supination means rotation of the forearm such that the palm of the hand faces forward or upward, and pronation means rotation of the forearm such that the palm of the hand faces backward or downward; the forearm with the hand is supinated or pronated at the elbow. Similar movements may be accomplished at the ankle, where supination results in the foot tipping inward relative to its long axis, and pronation results in the foot tipping outward; overpronation may contribute to the condition flatfoot. Circumduction refers to the circular movement of a joint or other organ, such as the wrist or the eye. Rotation is the movement of a body in such a way that the distance between a certain fixed point and any given point of that body remains constant. ... Elbow redirects here. ... The bones in the foot In anatomy, the ankle is the part of the lower limb that is located between the foot and the leg. ... Flatfoot is a description of foot position using the medial arch as a reference point. ... In human anatomy, the wrist is the flexible and narrower connection between the forearm and the hand. ... An eye is an organ that detects light. ...

An anterograde motion is in the normal direction of flow, while retrograde means reversed flow. For example, passage of food from the mouth to the stomach is in an anterograde direction, and gastric reflux is in a retrograde direction. Gastroesophageal Reflux Disease (GERD, or GORD when -oesophageal, the BE form, is substituted) is injury to the esophagus that develops from chronic exposure of the esophagus to acid coming up from the stomach (reflux). ...

See also

• Nomina Anatomica Veterinaria