organ of Giraldés
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organ(or'gan) [L. organum fr Gr. organon, tool, (musical) instrument, (bodily) organ]
A body structure made of several tissues that all contribute to specific functions. Many organs occur in pairs. In such pairs, one organ may be extirpated and the remaining one can perform all necessary functions peculiar to it. One third to two fifths of some organs may be removed without loss of function necessary to support life. See: table
An organ that has a subordinate function.
acoustic organSee: Corti, Alfonso Giacomo Gaspare
organ of CortiSee: Corti, Alfonso Giacomo Gaspare
A cup-shaped structure that forms on the tooth buds of an embryo. It produces the enamel and serves as a mold for the remainder of the tooth.
The expanded end of a nerve fiber in a peripheral structure.
An organ that is concerned with the excretion of waste products from the body.See: excretion
organ of GiraldésParadidymis.
Golgi tendon organSee: Golgi, Camillo
The organ of taste; a taste bud.
organ of JacobsonSee: Jacobson, Ludwig
A structure composed principally of lymphatic tissue. It includes the lymph nodes, spleen, tonsils, and thymus.
The spleen, lymph nodes, thymus, Peyer patches, and tonsils, where more than 98% of T lymphocytes are found.See: T cell
neuromuscular end organ
A spindle-shaped bundle of specialized fibers in which sensory nerve fibers terminate in muscles.
neurotendinous end organ
A specialized tendon fasciculus in which sensory nerve fibers terminate in the tendon. Synonym: tendon spindle
Any organ concerned with the production of offspring. These include the primary organs (testes and ovaries) and accessory structures (penis and spermatic cord in the male and fallopian tubes, uterus, and vagina in the female).Synonym: sex organ
organ of RuffiniSee: Ruffini, Angelo
A sensory receptor; a structure consisting of specialized sensory nerve endings that are capable of reacting to a stimulus (an external or internal change) by generating nerve impulses that pass through afferent nerves to the central nervous system. These impulses may give rise to sensations or reflexly bring about responses in the body.
sensory end organ
Any of the special clusters of cells that form a capsule around the receptor ends of certain sensory axons and affect the response of the axons. They include Meissner corpuscles, Pacinian corpuscles, Ruffini corpuscles, and Golgi tendon organs.See: sensory receptor
sex organReproductive organ.
An internal organ that has a firm tissue consistency and is neither hollow (such as the organs of the gastrointestinal tract) nor liquid (such as blood). Such organs include the heart, kidney, liver, lungs, and pancreas.
special sense organs
Any of the organs of smell, taste, sight, balance, and hearing.
spiral organSee: Corti, Alfonso Giacomo Gaspare
1. An organ upon which a chemical or hormone acts.
2. An organ adversely affected by a disease or condition.
An organ that is underdeveloped in humans but is fully functional in some animals.
vomeronasal organJacobson organ. See: Jacobson, Ludwig
Weber organSee: Weber, Moritz I.
organs of ZuckerkandlSee: Zuckerkandl, Emil
|Adrenal gland||5 cm high||5 g|
|3 cm across|
|1 cm thick|
|Bladder||12 cm in diameter||500 ml (when moderately full)|
|Blood volume||? 4–6 L|
|? 3–5 L|
|Brain||? 1240–1680 g|
|? 1130–1570 g|
|Ear, external canal||2.5 cm long (from concha)|
|Eye||23.5 mm vertical diameter|
|24 mm anteroposterior diameter|
|Fallopian tube||10 cm|
|Gallbladder||7–10 cm long||30–50 ml|
|3 cm wide|
|Heart||12 × 8–9 × 6 cm||?280–340 g|
|6–7 m long|
|Intestines—large||1.5 m long|
|Intestines—vermiform appendix||2–20 cm long, average 9 cm|
|Intestines—rectum||12 cm long|
|Kidney||11 cm long||? 150 g|
|6 cm broad||? 135 g|
|3 cm thick|
|Larynx||? 44 × 43 × 36 mm|
|? 36 × 41 × 26 mm|
|Liver||? 1.4–1.8 kg||6500 ml|
|? 1.0–2.5 kg|
|Lung||Right 625 g|
|Left 565 g|
|Ovaries||3 × 1.5 × 1 cm||2–3.5 g|
|Pancreas||15 cm long||? 74–106 g|
|? 70–100 g|
|Parathyroid||6 × 3–4 × 1–2 mm||50 mg|
|Pharynx||12.5 cm long|
|Prostate||2 × 4 × 3 cm||8 g|
|Skeleton||Average adult male, 4957 g|
|Skull||Average (without teeth), 642 g||Variable ? 406 ml ? 207 ml|
|Spinal cord||42–45 cm long||30 g|
|Spleen||12 × 7 × 3–4 cm||150 g|
|Decreases with age|
|25 cm long||1500 ml|
|10 cm wide|
|Testes||4–5 × 2.5 × 3 cm||10.5–14 g|
|Thoracic duct||38–45 cm long|
|Thymus||Newborn, 10.9 g|
|10–15 yr, 29.5 g|
|20–25 yr, 18.6 g|
|Thyroid||Each lobe 5 × 3 × 2 cm||30 g total|
|Trachea||11 cm long|
|2–2.5 cm in diameter|
|Ureter||28–34 cm long|
|Urethra||? 17.5–20 cm long|
|? 4 cm long|
|Uterus||7.5 × 5.0 × 2.5 cm||30–40 g (nonpregnant)|
|Vagina||Anterior wall length 7.5 cm|
|Posterior wall length 9.0 cm|