organ of Giraldés

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(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

accessory organ

An organ that has a subordinate function.

acoustic organ

See: Corti, Alfonso Giacomo Gaspare

organ of Corti

See: Corti, Alfonso Giacomo Gaspare

enamel organ

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.

end organ

The expanded end of a nerve fiber in a peripheral structure.

excretory organ

An organ that is concerned with the excretion of waste products from the body.
See: excretion

organ of Giraldés


Golgi tendon organ

See: Golgi, Camillo

gustatory organ

The organ of taste; a taste bud.

organ of Jacobson

See: Jacobson, Ludwig

lymphatic organ

A structure composed principally of lymphatic tissue. It includes the lymph nodes, spleen, tonsils, and thymus.

lymphoid organs

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

reproductive organ

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 Ruffini

See: Ruffini, Angelo

sense organ

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 organ

Reproductive organ.

solid 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 organ

See: Corti, Alfonso Giacomo Gaspare

target organ

1. An organ upon which a chemical or hormone acts.
2. An organ adversely affected by a disease or condition.

vestigial organ

An organ that is underdeveloped in humans but is fully functional in some animals.

vomeronasal organ

Jacobson organ. See: Jacobson, Ludwig

Weber organ

See: Weber, Moritz I.

organs of Zuckerkandl

See: Zuckerkandl, Emil SOURCE: Adapted from Gray's Anatomy, ed 27. Lea & Febiger, Philadelphia, 1959; Gray's Anatomy, ed 37. Churchill Livingstone, London, 1987; Growth. Federation of American Societies for Experimental Biology, Washington, DC, 1962; Jandl, JH, Blood. Little, Brown and Co., Boston, 1987.
Adrenal gland5 cm high5 g
3 cm across
1 cm thick
Bladder12 cm in diameter500 ml (when moderately full)
Blood volume? 4–6 L
? 3–5 L
Brain? 1240–1680 g
? 1130–1570 g
Ear, external canal2.5 cm long (from concha)
Esophagus23–25 cm
Eye23.5 mm vertical diameter
24 mm anteroposterior diameter
Fallopian tube10 cm
Gallbladder7–10 cm long30–50 ml
3 cm wide
Heart12 × 8–9 × 6 cm?280–340 g
?230–280 g
6–7 m long
Intestines—large1.5 m long
Intestines—vermiform appendix2–20 cm long, average 9 cm
Intestines—rectum12 cm long
Kidney11 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 kg6500 ml
? 1.0–2.5 kg
LungRight 625 g
Left 565 g
Ovaries3 × 1.5 × 1 cm2–3.5 g
Pancreas15 cm long? 74–106 g
? 70–100 g
Parathyroid6 × 3–4 × 1–2 mm50 mg
Pharynx12.5 cm long
Prostate2 × 4 × 3 cm8 g
SkeletonAverage adult male, 4957 g
SkullAverage (without teeth), 642 gVariable ? 406 ml ? 207 ml
Spinal cord42–45 cm long30 g
Spleen12 × 7 × 3–4 cm150 g
80–300 g
Decreases with age
25 cm long1500 ml
10 cm wide
Testes4–5 × 2.5 × 3 cm10.5–14 g
Thoracic duct38–45 cm long
ThymusNewborn, 10.9 g
10–15 yr, 29.5 g
20–25 yr, 18.6 g
ThyroidEach lobe 5 × 3 × 2 cm30 g total
Trachea11 cm long
2–2.5 cm in diameter
Ureter28–34 cm long
Urethra? 17.5–20 cm long
? 4 cm long
Uterus7.5 × 5.0 × 2.5 cm30–40 g (nonpregnant)
VaginaAnterior wall length 7.5 cm
Posterior wall length 9.0 cm
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