In biological morphology and

anatomy Anatomy () is the branch of morphology concerned with the study of the internal structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old scien ...

, a sulcus (: sulci) is a furrow or fissure (

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

''fissura'', : ''fissurae''). It may be a groove, natural division, deep furrow, elongated cleft, or tear in the surface of a limb or an organ, most notably on the surface of the

brain The brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for ...

, but also in the

lung The lungs are the primary Organ (biology), organs of the respiratory system in many animals, including humans. In mammals and most other tetrapods, two lungs are located near the Vertebral column, backbone on either side of the heart. Their ...

s, certain

muscle Muscle is a soft tissue, one of the four basic types of animal tissue. There are three types of muscle tissue in vertebrates: skeletal muscle, cardiac muscle, and smooth muscle. Muscle tissue gives skeletal muscles the ability to muscle contra ...

s (including the

heart The heart is a muscular Organ (biology), organ found in humans and other animals. This organ pumps blood through the blood vessels. The heart and blood vessels together make the circulatory system. The pumped blood carries oxygen and nutrie ...

), as well as in bones, and elsewhere. Many sulci are the product of a surface fold or junction, such as in the

gums The gums or gingiva (: gingivae) consist of the mucosal tissue that lies over the mandible and maxilla inside the mouth. Gum health and disease can have an effect on general health. Structure The gums are part of the soft tissue lining of the ...

, where they fold around the

neck The neck is the part of the body in many vertebrates that connects the head to the torso. It supports the weight of the head and protects the nerves that transmit sensory and motor information between the brain and the rest of the body. Addition ...

of the tooth. In

invertebrate zoology Invertebrate zoology is the subdiscipline of zoology that consists of the study of invertebrates, animals without a backbone (a structure which is found only in fish, amphibians, reptiles, birds and mammals). Invertebrates are a vast and very dive ...

, a sulcus is a fold, groove, or boundary, especially at the edges of

sclerite A sclerite (Greek language, Greek , ', meaning "hardness, hard") is a hardened body part. In various branches of biology the term is applied to various structures, but not as a rule to vertebrate anatomical features such as bones and teeth. Instea ...

s or between segments. In

pollen Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced Gametophyte#Heterospory, microgametophytes), which produce male gametes (sperm ...

, a grain that is grooved by a sulcus is termed

sulcate Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains ...

Examples in anatomy

Liver

* Ligamentum teres hepatis fissure *

Ligamentum venosum The ligamentum venosum, also known as Arantius' ligament, is the fibrous remnant of the ductus venosus of the fetal circulation. Usually, it is attached to the left branch of the portal vein within the porta hepatis. It may be continuous with the ...

fissure * Portal fissure, found in the under-surface of the

liver The liver is a major metabolic organ (anatomy), organ exclusively found in vertebrates, which performs many essential biological Function (biology), functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of var ...

* Transverse fissure of liver, found in the lower surface of the liver *

Umbilical fissure Umbilical may refer to: Biology *Umbilical cord * Umbilical fold *Umbilical hernia * Umbilical notch *Umbilical vessels **Umbilical artery **Umbilical vein * Umbilical zone *Umbilical region Other * Umbilical cable, in engineering * The Um ...

, found in front of the

Lung

*Azygos fissure, of right lung * Horizontal fissure of right lung *

Oblique fissure The lungs are the primary organs of the respiratory system in many animals, including humans. In mammals and most other tetrapods, two lungs are located near the backbone on either side of the heart. Their function in the respiratory syste ...

, of the right and left lungs

Skull

Auricular fissure Auricular may refer to: Medicine and anatomy * Auricular muscles, surrounding the ear * A relational adjective, as in the auricular branch of vagus nerve, used to delineate a relationship to the ear and its structures ** Auricular branch (disamb ...

, found in the

temporal bone The temporal bone is a paired bone situated at the sides and base of the skull, lateral to the temporal lobe of the cerebral cortex. The temporal bones are overlaid by the sides of the head known as the temples where four of the cranial bone ...

Petrotympanic fissure The petrotympanic fissure (also known as the squamotympanic fissure or the glaserian fissure) is a fissure in the temporal bone that runs from the temporomandibular joint to the tympanic cavity. The mandibular fossa is bounded, in front, by the ...

Pterygomaxillary fissure The pterygomaxillary fissure is a fissure of the human skull. It is vertical, and descends at right angles from the medial end of the inferior orbital fissure. It is a triangular interval, formed by the divergence of the maxilla from the pterygoi ...

* Sphenoidal fissure, separates the wings and the body of the sphenoid bone * Superior orbital fissure

Other types

* anal fissure, a break or tear in the skin of the anal canal * anterior interventricular sulcus * calcaneal sulcus * coronal sulcus * femoral sulcus or

intercondylar fossa of femur The intercondylar fossa of femur (intercondyloid fossa of femur, intercondylar notch of femur) is a deep notch between the rear surfaces of the medial and lateral epicondyle of the femur, two protrusions on the distal end of the femur (thigh bon ...

* fissure (dentistry), a break in the tooth enamel * fissure of the nipple, a condition that results from running, breastfeeding and other friction-causing exposures * fissured tongue, a condition characterized by deep grooves (fissures) in the tongue *

gingival sulcus In dental anatomy, the gingival sulcus is an area of potential space between a tooth and the surrounding gingiva, gingival tissue and is lined by sulcular epithelium. The depth of the sulcus (Latin for ''groove'') is bounded by two entities: ...

gluteal sulcus The gluteal sulcus (also known as the gluteal fold, tuck, fold of the buttock, horizontal gluteal crease, or gluteal furrow) is an area of the body of humans and anthropoid apes, described by a horizontal crease formed by the inferior aspect of t ...

* Henle's fissure, a fissure in the connective tissue between the muscle fibers of the

* interlabial sulci *

intermammary sulcus The intermammary cleft, intermammary sulcus, or sulcus intermammarius is a Surface anatomy, surface feature of males and females that marks the division of the two breasts with the sternum (breastbone) in the middle.Dr. Ted Eisenberg and Joyce K. ...

* intertubercular sulcus, the groove between the lesser and greater tubercules of the humerus (bone of the upper arm) * lacrimal sulcus (sulcus lacrimalis) * malleolar sulcus *

palpebral fissure The palpebral fissure is the elliptic space between the medial and lateral canthi of the two open eyelids. In simple terms, it is the opening between the eyelids. In adult humans, this measures about 10 mm vertically and 30 mm horizontally. Va ...

, separates the upper and lower eyelids * patellar sulcus or

posterior interventricular sulcus The posterior interventricular sulcus or posterior longitudinal sulcus is one of the two grooves separating the ventricles of the heart (the other being the anterior interventricular sulcus). They can be known as subsinosal interventricular groo ...

* preauricular sulcus * radial sulcus ( musculospiral groove) * sagittal sulcus * separatoral sulcus (depression behind the brow ridges of some primates) * sigmoid sulcus * skin fissure, a linear-like cleavage of skin, sometimes defined as extending into the dermis * sulcus arteriæ vertebralis *

sulcus subtarsalis Sulcus subtarsalis is a groove in the inner surface of eyelid near the eyelid margin and which is also parallel to it. This separates marginal conjunctiva from tarsal conjunctiva. It provides space for lodging of foreign bodies. Arlt's line is a ...

in the eyelid *

sulcus tubae auditivae The lateral half of the great wing of the sphenoid bone articulates, by means of a synchondrosis, with the petrous part of the temporal bone. Between these two bones on the under surface of the skull, is a furrow, the sulcus of auditory tubule'', ...

* tympanic sulcus * urethral sulcusLarkins, Christine E., and Martin J. Cohn.
Phallus development in the turtle Trachemys scripta
" Sexual Development 9.1 (2015): 34-42. * ventral median fissure, of the spinal cord

In neuroanatomy

Brain

*'' Broca's fissure'': found in the third left frontal fold of the brain. *'' Burdach's fissure'': connects the brain's insula and the inner surface of the operculum. *'' Calcarine sulcus'' or ''Calcerine fissure'': extends from the occipital of the

cerebrum The cerebrum (: cerebra), telencephalon or endbrain is the largest part of the brain, containing the cerebral cortex (of the two cerebral hemispheres) as well as several subcortical structures, including the hippocampus, basal ganglia, and olfac ...

to the occipital fissure. *'' Callosomarginal fissure'': found in the medial surface of the cerebrum. *''

Central sulcus In neuroanatomy, the central sulcus (also central fissure, fissure of Rolando, or Rolandic fissure, after Luigi Rolando) is a sulcus, or groove, in the cerebral cortex in the brains of vertebrates. It is sometimes confused with the longitudinal ...

'' or ''Rolando's fissure'': separates the brain's frontal and

parietal lobe The parietal lobe is one of the four Lobes of the brain, major lobes of the cerebral cortex in the brain of mammals. The parietal lobe is positioned above the temporal lobe and behind the frontal lobe and central sulcus. The parietal lobe integra ...

s. *'' Clevenger's fissure'': found in the inferior temporal lobe of the brain *''

Collateral fissure The collateral fissure is a large sulcus on the tentorial surface of the cerebral hemisphere and extends from near the occipital pole to within a short distance of the temporal pole. It is also known as the medial occipitotemporal sulcus. Beh ...

'': found in the inferior surface of the cerebrum. *'' Fissure of Bichat'': found below the

corpus callosum The corpus callosum (Latin for "tough body"), also callosal commissure, is a wide, thick nerve tract, consisting of a flat bundle of commissural fibers, beneath the cerebral cortex in the brain. The corpus callosum is only found in placental ...

in the

cerebellum The cerebellum (: cerebella or cerebellums; Latin for 'little brain') is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as it or eve ...

of the

. *''

Lateral sulcus The lateral sulcus (or lateral fissure, also called Sylvian fissure, after Franciscus Sylvius) is the most prominent sulcus (neuroanatomy), sulcus of each cerebral hemisphere in the human brain. The lateral sulcus (neuroanatomy), sulcus is a deep ...

'' or ''Fissure of Sylvius'': separates the frontal and parietal lobes of the brain from the temporal lobe. *'' Hippocampal sulcus'': a sulcus that extends from the brain's corpus callosum to the tip of the temporal lobe. *'' Horizontal fissure or Transverse fissure'': found between the cerebrum and the cerebellum. Note that a "transverse fissure" can also be found in the

and

s. *''

Longitudinal fissure The longitudinal fissure (or cerebral fissure, great longitudinal fissure, median longitudinal fissure, interhemispheric fissure) is the deep groove that separates the two cerebral hemispheres of the vertebrate brain. Lying within it is a continu ...

'' or ''Medial longitudinal fissure'': which divides the cerebrum into the two hemispheres. *'' Occipitoparietal fissure'': found between the occipital and parietal lobes of the brain. *'' Wernicke's fissure'': separates the brain's temporal and parietal lobes from the occipital lobe. *'' Zygal fissure'': found in the cerebrum. In the

, a sulcus is a groove formed in the stage of

gyrification Gyrification is the process of forming the characteristic folds of the cerebral cortex. The peak of such a fold is called a ''gyrus'' (pl. ''gyri''), and its trough is called a ''Sulcus (neuroanatomy), sulcus'' (pl. ''sulci''). The neurons of the ...

by the folding of the

cortex Cortex or cortical may refer to: Biology * Cortex (anatomy), the outermost layer of an organ ** Cerebral cortex, the outer layer of the vertebrate cerebrum, part of which is the ''forebrain'' *** Motor cortex, the regions of the cerebral cortex i ...

. There are many sulci and

gyri In neuroanatomy, a gyrus (: gyri) is a ridge on the cerebral cortex. It is generally surrounded by one or more sulcus (neuroanatomy), sulci (depressions or furrows; : sulcus). Gyri and sulci create the folded appearance of the brain in huma ...

formed. A larger than usual sulcus may instead be called a

fissure A fissure is a long, narrow crack opening along the surface of Earth. The term is derived from the Latin word , which means 'cleft' or 'crack'. Fissures emerge in Earth's crust, on ice sheets and glaciers, and on volcanoes. Ground fissure A ...

such as the

longitudinal fissure The longitudinal fissure (or cerebral fissure, great longitudinal fissure, median longitudinal fissure, interhemispheric fissure) is the deep groove that separates the two cerebral hemispheres of the vertebrate brain. Lying within it is a continu ...

that separates the two hemispheres.

References

{{DEFAULTSORT:Sulcus (Anatomy) Anatomy