placode


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placode

 [plak´ōd]
a platelike structure, especially a thickening of the ectoderm marking the site of future development in the early embryo of an organ of special sense, e.g., the auditory placode (ear), lens placode (eye), and olfactory placode (nose).

plac·ode

(plak'ōd),
Local thickening in the embryonic ectodermal layer; the cells of the placode ordinarily constitute a primordial group from which a sense organ or ganglion develops.
[G. plakōdēs, fr. plax, anything flat or broad, + eidos, like]

placode

/plac·ode/ (plak´ōd) a platelike structure, especially a thickened plate of ectoderm in the early embryo, from which a sense organ develops, e.g., otic p. (ear), lens p. (eye), and nasal p. (nose).

plac·ode

(plak'ōd)
Local thickening in the embryonic ectodermal layer; the cells of the placode ordinarily constitute a primordial group from which a sense organ or ganglion develops.
[G. plakōdēs, fr. plax, anything flat or broad, + eidos, like]

placode

a plate-like embryonic structure from which a particular organ, such as the eye, develops.

placode

a platelike structure, especially a thickening of the ectoderm marking the site of future development in the early embryo of an organ of special sense, e.g. the auditory placode (ear), lens placode (eye) and olfactory placode (nose).

lens placode
the ectodermal thickening which develops into the lens vesicle and later the lens.
nasal placode
one of a pair of ectodermal thickenings which are the forerunners of the external nares and nasopharyngeal epithelium.
olfactory placode
an ectodermal thickening of the embryo which ultimately provides the sensory nerves for the olfactory region of the nasal mucosa.
otic placode
one of the pair of ectodermal thickenings in the vertebrate embryo which invaginates and is a major contributor to the internal ear.
References in periodicals archive ?
The palp, an adhesive organ differentiated in the anterior tip of the larva, is considered to have the same origin as the vertebrate anterior placodes.
It has been suggested that the ascidians possess neural crest and placodes (Jeffery et al.
From shared lineage to distinct functions: the development of the inner ear and epibranchial placodes.
The goal of the zebrafish research is to understand at the molecular level, how and why otic placode cells decide to become neuronal, non-sensory or sensory cells.
1) They are derived from different embryologic cell anlages: the epibranchial placode of the second branchial arch and the neural crest of the facial primordium, respectively.
OECs develop from the olfactory placode and subsequently migrate into the olfactory nerve and OB.
As seen in many other organs of epithelial origin, the cells of the thyroid placode contain thick bands of microfilaments just below the apical and basal surfaces (Shain and others 1972; Hilfer 1973).
Induction and intubation should be done in lateral position or supine position by putting the placode within a padding made in shape of a doughnut to avoid its rupture.
The development of porcine breast was mainly composed of the formation and specialization of milk line, formation of mammary placode, glandular bud and primitive ductal branching (Balinsky, 1950).
The lesion should be covered with a warm saline-soaked dressing to protect the placode and prevent desiccation.
Embryologically, the VNO is derived from the olfactory placode (Bossy, 1980;6 Garrosa, 1998).
Flattening the ring of cells causes the interior of the placode to telescope outward, forming a tentacle that the sea anemone will use to catch food.