| Exocrine gland | |
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| Human submaxillary gland. At the right is a group of mucous alveoli, at the left a group of serous alveoli. |
Exocrine glands are glands that secrete their products (enzymes) into ducts (duct glands). A gland is an organ in an animal's body that synthesizes a substance for release such as Hormones or Breast milk, often into the Bloodstream Enzymes are Biomolecules that catalyze ( ie increase the rates of Chemical reactions Almost all enzymes are Proteins In Anatomy and Physiology, a duct is a circumscribed channel leading from an Exocrine gland or organ. They are the counterparts to endocrine glands, which secrete their products (hormones) directly into the bloodstream (ductless glands) or release hormones (paracrines) affect only target cell near the release site by. Endocrine glands are Glands that secrete their product ( Hormones, directly into the blood rather than through a duct Hormones (from Greek ὁρμή - "impetus" are chemicals released by cells that affect cells in other parts of the body Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells such as nutrients and oxygen—and transports Waste products Paracrine signaling is a form of Cell signaling in which the target cell is near (" Para " = near the signal-releasing cell
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Examples
Typical exocrine glands include sweat glands, salivary glands, mammary glands, stomach, liver and the pancreas. The skin contains two different groups of sweat glands: Apocrine sweat glands and Merocrine sweat glands. The salivary glands in mammals are exocrine glands that produce saliva Mammary glands are the organs that in Mammals produce Milk for the sustenance of the young In Human anatomy, the stomach is a J-shaped hollow muscular organ of the Gastrointestinal tract involved in the second phase of Digestion, following The liver is a vital organ in the human body and is present in Vertebrates and some other animals The pancreas is a Gland organ in the digestive and Endocrine system of Vertebrates. (Example of an endocrine gland is the adrenal gland, which is found on top of the kidneys and secretes the hormone adrenaline).
Types
There are multiple ways of classifying exocrine glands:
Structure
Exocrine glands contain a glandular portion and a duct portion, the structures of which can be used to classify the gland.
- The duct portion may be branched (called compound) or unbranched (called simple).
- The glandular portion may be tubular, acinar, or may be a mix of the two (called tubuloacinar). An acinus (adjective acinar, plural acini) refers to the berry-shaped termination of an Exocrine gland, where the secretion is produced If the glandular portion branches, then the gland is called a branched gland.
Method of secretion
Exocrine glands are named apocrine gland, holocrine gland, or merocrine gland based on how their product is secreted. Holocrine is a classification of Exocrine glands in the study of Histology. Merocrine ( eccrine) is a classification of Exocrine glands in the study of Histology.
- Apocrine glands - a portion of the plasma membrane buds off the cell, containing the secretion. Apocrine gland is often used to refer to the apocrine sweat glands which use merocrine secretion.
- Holocrine glands - the entire cell disintegrates to secrete its substance.
- Merocrine glands - cells secrete their substances by exocytosis. Exocytosis (ek-soh-sy-TOH-sis Greek: Έξω - external and κύτος - cell is the durable process by which a cell directs secretory vesicles out of the Cell Also called "eccrine. "
Product secreted
- Serous cells secrete proteins, often enzymes. Proteins are large Organic compounds made of Amino acids arranged in a linear chain and joined together by Peptide bonds between the Carboxyl Enzymes are Biomolecules that catalyze ( ie increase the rates of Chemical reactions Almost all enzymes are Proteins Examples include chief cells and Paneth cells
- Mucous cells secrete mucus. In general a chief cell (or a " Zymogenic cell" is a cell which releases a precursor Enzyme. Paneth cells provide host defense against Microbes in the Small intestine. In vertebrates mucus is a slippery secretion produced by and covering Mucous membranes It is a viscous Colloid containing Antiseptic enzymes (such as Examples include Brunner's glands, esophageal glands, and pyloric glands
- Mixed glands secrete both protein and mucus. Brunner glands (or Pancreal glands) are compound tubular submucosal Glands found in that portion of the Duodenum which is above the The esophageal glands are small compound Racemose Exocrine glands of the Mucous type The pyloric glands are found in the Pyloric portion of the Stomach. Examples include the salivary glands, although parotid gland is predominantly serous, the sublingual gland is predominantly mucous and the submandibular gland is both serous and mucous. The salivary glands in mammals are exocrine glands that produce saliva For the toad wart see Parotoid gland. The parotid gland is the largest of the Salivary glands It is found wrapped around the Mandibular ramus The sublingual glands are Salivary glands in the Mouth. They lie anterior to the Submandibular gland under the Tongue, beneath the Mucous
List of exocrine glands
Glands typically may be referred to by two or more means, though some terms are rarely seen. The names of the anatomists who first described them are often employed, as:
| name(s) | location | product | structure |
| apocrine sweat glands | skin | - | coiled tubular |
| Bartholin's glands, Tiedmann's glands, vulvovaginal glands | vulva, vagina | - | - |
| Bauhin's glands, anterior lingual glands | tongue, near tip | nonserous or mixed | - |
| Brunner's glands, duodenal glands | duodenum | mucous | compound tubular |
| bulbourethral glands, Cowper's glands, Mery's glands | penis, base | - | - |
| Ciaccio's glands, accessory lacrimal glands | eye | - | - |
| Cobelli's glands | esophagus, just above the cardia, in the mucosa | mucous | - |
| Duverney's gland | vagina, on either side | - | - |
| Ebner's glands | tongue | serous | - |
| eccrine sweat glands | skin | - | coiled tubular |
| esophageal glands | esophagus | mucous | racemose |
| exocrine pancreas | pancreas | serous | tubulo-acinar |
| Fränkel's glands | vocal cords, below the edge | - | - |
| gastric chief cell, Wasmann's glands | stomach | serous | - |
| glomus coccygeum, coccygeal gland, Luschka's gland or ganglion | coccyx, near the tip | - | - |
| goblet cells | digestive tract, respiratory tract | mucous | simple unicellular |
| Henle's glands | eyelids, in the conjuctiva | - | tubular |
| Huguier's glands | vagina | - | - |
| Krause's glands | conjunctiva, middle portion | mucous | - |
| Lieberkuhn's glands | intestines, surface of mucous membrane | - | simple tubular |
| Littré's glands, Morgagni's glands | spongy portion of the urethra | - | racemose |
| mammary gland | breast | - | compound tubulo-acinar |
| Meibomian gland | eyelids | sebaceous | - |
| Moll's glands | eyelids | - | - |
| Montgomery's glands | mammary areola | sebaceous | - |
| Naboth's glands | cervix and os uteri | mucous | - |
| olfactory glands, Bowman's glands | nose, olfactory region | - | - |
| Paneth cells | small intestine | serous | - |
| parathyroid glands, Gley's glands, Sandstroem's glands | thyroid, on surface | - | - |
| parotid gland | mouth | serous | tubulo-alveolar |
| Peyer's patches (or glands) | ileum, lymphatic glands | - | - |
| pyloric glands | stomach | mucous | simple branched tubular |
| sebaceous gland | skin | sebum | acinar - branched |
| Skene's glands, Guérin's glands | vagina | - | - |
| sublingual gland, Rivini's gland | mouth | mucus (primarily) | tubulo-alveolar |
| submandibular gland | mouth | mixed (M+S) | tubulo-alveolar |
| sudoriparous glands, Boerhaave's glands | skin | - | - |
| Sigmund's glands | epitrochlear lymph nodes | - | - |
| Suzanne's gland | mouth, beneath the alveolingual groove | mucous | - |
| Weber's glands | tongue | mucous | tubular |
| Glands of Zeis | eyelids, free edges | sebaceous | - |
See also
- Wikipedia:MeSH A10#MeSH A10.336 --- exocrine glands
Prostate gland is an exocrine gland of the male mammalian reproductive system. Anatomy (from the Greek anatomia, from ana separate apart from and temnein, to cut up cut open is a branch of Biology that is the consideration The skin is the outer covering of living tissue of an animal (or plant The Bartholin's glands (also called Bartholin glands or greater vestibular glands) are two Glands located slightly below and to the left and right of the The vulva (from Latin, vulva, plural vulvae or vulvas; see etymology) is the region of the external genital organs The vagina (from Latin, literally " Sheath " or " Scabbard " is a fibromuscular tubular tract leading from the Uterus Anterior lingual glands (also called apical glands) are deeply placed Seromucous glands that are located near the tip of the Tongue on each side of the The tongue is the large bundle of Skeletal muscles on the floor of the Mouth that manipulates Food for chewing and swallowing (deglutition Brunner glands (or Pancreal glands) are compound tubular submucosal Glands found in that portion of the Duodenum which is above the In Anatomy of the Digestive system, the duodenum is a hollow jointed tube about 25-30 cm (10-12 in long connecting the Stomach to the Jejunum A bulbourethral Gland (or Cowper 's gland) is one of two small Exocrine glands present in the Reproductive system of human males The penis (plural penises, penes Ciaccio's glands are small tubular accessory Lacrimal glands ( glandulae lacrimales accessoriae) found in the lacrimal Caruncle of the Eyelid. The lacrimal glands are paired almond-shaped Glands, one for each eye that secrete the aqueous layer of the tear film Eyes are organs that detect Light, and send signals along the Optic nerve to the visual areas of the brain The esophagus or oesophagus (see American and British English spelling differences) sometimes known as the gullet, is an organ in The cardia (also known as Z-line or esophagogastric junction or gastroesophageal junction) is the anatomical term for the junction orifice of The mucous membranes (or mucosae; singular mucosa) are linings of mostly endodermal origin covered in Epithelium, which are involved in The vagina (from Latin, literally " Sheath " or " Scabbard " is a fibromuscular tubular tract leading from the Uterus Ebner's glands are Exocrine glands found in the mouth More specifically they are serous Salivary glands which reside within the moats surrounding the The tongue is the large bundle of Skeletal muscles on the floor of the Mouth that manipulates Food for chewing and swallowing (deglutition Eccrine sweat glands (sometimes merocrine sweat glands) are Coiled tubular glands derived from the outer layer of skin but extending into the inner layer used The skin is the outer covering of living tissue of an animal (or plant The esophageal glands are small compound Racemose Exocrine glands of the Mucous type The esophagus or oesophagus (see American and British English spelling differences) sometimes known as the gullet, is an organ in The Exocrine Pancreas has ducts that are arranged in clusters called Acini (singular acinus) The pancreas is a Gland organ in the digestive and Endocrine system of Vertebrates. The vocal folds, also known commonly as vocal cords, are composed of twin infoldings of Mucous membrane stretched horizontally across the Larynx. A Gastric chief cell (or peptic cell, or gastric zymogenic cell) is a cell in the Stomach that releases Pepsinogen, gastric lipase and In Human anatomy, the stomach is a J-shaped hollow muscular organ of the Gastrointestinal tract involved in the second phase of Digestion, following The coccygeal glomus ( coccygeal gland or body; Luschka’s gland) is placed in front of or immediately below the tip of the Coccyx. The coccyx (pronounced kok -siks (Latin os coccygis) commonly referred to as the tailbone, is the final segment of the human vertebral column Goblet cells are Glandular simple columnar epithelial cells whose sole function is to secrete Mucus. In humans the respiratory tract is the part of the Anatomy that has to do with the process of respiration. Crypts of Henle are microscopic pockets found in scattered sections of the Conjunctiva around the Eyeball. An eyelid is a thin fold of skin that covers and protects an Eye. The conjunctiva is a clear membrane that covers the Sclera (white part of the Eye) and lines the inside of the Eyelids It is made of lymphoid tissue The vagina (from Latin, literally " Sheath " or " Scabbard " is a fibromuscular tubular tract leading from the Uterus Krause's glands are small mucous accessory Lacrimal glands that are found underneath the Eyelid where the upper and lower conjuctivae meet The conjunctiva is a clear membrane that covers the Sclera (white part of the Eye) and lines the inside of the Eyelids It is made of lymphoid tissue The crypts of Lieberkühn (or intestinal glands) are Glands found in the Epithelial lining of the Small intestine and colon. In Anatomy, the intestine is the segment of the alimentary canal extending from the Stomach to the Anus and in humans and other mammals consists The mucous membranes (or mucosae; singular mucosa) are linings of mostly endodermal origin covered in Epithelium, which are involved in The term urethral or periurethral gland (also Littre gland after Alexis Littré, or preputial glands) is used to refer to any of the many Glands The spongy urethra ( cavernous portion of urethra, penile urethra) is the longest part of the male Urethra, and is contained in the Corpus spongiosum A raceme is a type of Inflorescence that is unbranched and indeterminate and bears pedicellate Flowers &mdash flowers having short Mammary glands are the organs that in Mammals produce Milk for the sustenance of the young The breast is the upper Ventral region of an animal’s Torso, particularly that of Mammals including Human beings. The meibomian glands (or tarsal glands) are a special kind of Sebaceous glands at the rim of the Eyelids responsible for the supply of Sebum, An eyelid is a thin fold of skin that covers and protects an Eye. Glands of Moll, also known as ciliary glands, are modified Apocrine Sweat glands that are found on the margin of the Eyelid. An eyelid is a thin fold of skin that covers and protects an Eye. Glands of Montgomery are Sebaceous glands in the Areola (of the Nipple) This aritcle is about the breast tissue For the Entomology term see Glossary of Lepidopteran_terms#Wings. A nabothian cyst (or nabothian follicle) is a mucus-filled cyst on the surface of the Cervix. The cervix (from Latin "neck" is the lower narrow portion of the Uterus where it joins with the top end of the Vagina. The external orifice of the uterus (or ostium of uterus, or external os) is a small depressed somewhat circular aperture on the rounded extremity of the Beneath the Epithelium, and extending through the thickness of the Mucous membrane, is a layer of tubular often branched glands the olfactory glands ( glands Anatomically a nose is a protuberance in Vertebrates that houses the Nostrils or nares which admit and expel air for respiration in conjunction with the Olfaction (also known as olfactics or smell) refers to the Sense of smell. Paneth cells provide host defense against Microbes in the Small intestine. In Biology the small Intestine is the part of the Gastrointestinal tract (gut between the Stomach and the Large intestine, and comprises The parathyroid glands are small endocrine Glands in the neck usually located behind the Thyroid gland, which produce Parathyroid hormone. The thyroid is one of the largest Endocrine glands in the body For the toad wart see Parotoid gland. The parotid gland is the largest of the Salivary glands It is found wrapped around the Mandibular ramus The mouth, buccal cavity, or oral cavity is the first portion of the Alimentary canal that receives food and begins digestion by mechanically breaking up Peyer's patches are secondary lymphoid tissue named after the 17th-century Swiss anatomist Johann Conrad Peyer. In Anatomy of the Digestive system, the ileum is the final section of the Small intestine. The lymphatic system in Vertebrates is a network of conduits that carry a clear fluid called Lymph. The pyloric glands are found in the Pyloric portion of the Stomach. In Human anatomy, the stomach is a J-shaped hollow muscular organ of the Gastrointestinal tract involved in the second phase of Digestion, following The sebaceous glands are Glands found in the Skin of Mammals Locations and morphology A branched type of Acinar gland, these The skin is the outer covering of living tissue of an animal (or plant In Human anatomy (female the Skene's glands (also known as the lesser vestibular, periurethral glands, skene glands, paraurethral The vagina (from Latin, literally " Sheath " or " Scabbard " is a fibromuscular tubular tract leading from the Uterus The sublingual glands are Salivary glands in the Mouth. They lie anterior to the Submandibular gland under the Tongue, beneath the Mucous The mouth, buccal cavity, or oral cavity is the first portion of the Alimentary canal that receives food and begins digestion by mechanically breaking up The paired submandibular glands (or submaxillary glands) are Salivary glands located beneath the floor of the mouth The mouth, buccal cavity, or oral cavity is the first portion of the Alimentary canal that receives food and begins digestion by mechanically breaking up The skin contains two different groups of sweat glands: Apocrine sweat glands and Merocrine sweat glands. The skin is the outer covering of living tissue of an animal (or plant A Lymph node ( lɪmf noʊd is an organ consisting of many types of cells and is a part of the Lymphatic system. The tongue is the large bundle of Skeletal muscles on the floor of the Mouth that manipulates Food for chewing and swallowing (deglutition Glands of Zeis are unilobar Sebaceous glands located on the margin of the Eyelid. An eyelid is a thin fold of skin that covers and protects an Eye. It secretes a clear and basic fluid that constitutes 1/3 of the volume of semen.
Additional images
 Section of the human esophagus. Moderately magnified. |  Dissection of a lactating breast. |
References
External links
- Diagram at mhhe.com
- gland at eMedicine Dictionary
Dictionary
exocrine gland
-noun
- (anatomy) Any of various glands which secrete via a duct, typically into the digestive tract or onto the skin.
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