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of cortical structure(s) to be determined by the 
preexisting organization of the cytoplasm in the 
particular site concerned; the ordering and arrang-
ing of new cell structure under the influence of 
pre-existing cell structure; see also Structural
Guidance Principle . 
Dactylophrya – Stage : see Dactylozoite . 
Dactylozoite : infective stage in the most unusual 
life cycle of the suctorian Tachyblaston ; dactylozoi-
tes arise by several rapid fissions of the loricate 
parental organism, and then, though non-ciliated 
and with but one tentacle, reach the body of another 
suctorian, Ephelota , “burrow” in, and develop into 
forms producing a ciliated swarmer stage; swarmers 
settle down, often on the stalk of the same Ephelota , 
produce their own stalk and lorica, and repeat the 
cycle; a synonym is Dactylophrya -stage. 
Dargyrome : argyrome on the dorsal surface of 
hypotrich spirotrichs. 
Daughter Organisms : see Filial Products . 
Deme : population within a species; the concept is 
particularly used by parasitologists to indicate popu-
lations of different types: (e.g. monodeme, nosodeme, 
serodeme, topodeme, and xenodeme); the organisms 
comprising different demes may possess distinctive 
morphological and/or physiological characters and, 
in some cases, may be incipient subspecies or even 
unrecognized biological species. 
Dendritic Colony : synonym of arboroid colony . 
Dendroid Colony : synonym of arboroid colony . 
De Novo Cytoplasmic : now discarded term for a 
mode of stomatogenesis ; see Telokinetal for its 
modified replacement. 
De Novo Kinetosomal : now discarded term for a 
mode of stomatogenesis ; see Apokinetal . 
Denticle : one of many similar structures or inter-
locked component parts of a supporting ring under-
lying the adhesive disc of mobiline peritrichs; 
a proteinaceous subpellicular skeletal element 
composed of a conical centrum and typically an 
inwardly directed spine or ray and outwardly 
directed blade (Dent, Fig. 2.9Bg, 2.9Bh). 
Denticulate Ring : skeletal organelle, made up of 
denticles , found in mobiline peritrichs ; see Denticle
(Fig. 2.4L). 
Derived Character : see Apomorphy . 
Desmodexy, Rule of : true kinetodesmata , when 
present, lie to or extend anteriad and/or to the 
organism’s right of the kinety with which they are 
associated; thus, polarity of the cell can be deduced 
(see Bipolar Kinety ) (Figs. 2.1, 2.2). 
Detritivorous : feeding on organic particles. 
Deuterostomisation : an evolutionary process in 
which oral kinetosomes are formed anew from 
somatic kinetosomes after the loss of the original 
oral ciliature; supposed to have occurred in lito-
stomes and phyllopharyngeans . 
Diastole : see Contractile Vacuole . 
Dictyosome : see Golgi Apparatus . 
Dikinetid : a kinetid composed of two kinetosomes
and their fibrillar associates; see Dyad , Monokinetid , 
and Polykinetid (Figs. 2.1E, 2.2c, 2.2d). 
Diploid : 2N number of chromosomes; character-
istic of ciliate micronuclei whose chromosomes 
may be visible and enumerated at mitosis, although 
the true ploidy of many ciliates is unknown; see 
Haploid . 
Glossary 27
Diplokinety (pl. Diplokineties ): often, applied 
to a kinety with its kinetosomes doubled in some 
specific fashion; see Diplostichomonad . 
Diplostichomonad : type of double paroral whose 
infraciliature is composed of two parallel rows or 
files of kinetosomes – the inner or endoral membrane 
and the outer or paroral membrane ; the kinetosomes 
are never in dyads nor do they form a zigzag pattern, 
and all are ciliferous ; a type of diplokinety ; charac-
teristic condition of clevelandellid armophoreans , 
many hypotrichs , and many stichotrichs . 
Director-meridian : argentophilic non-kinetosomal
line on the midventral surface, coursing from 
the posterior margin of the buccal cavity to the 
cytoproct near the posterior end of the body; 
occasionally with non-ciliferous basal bodies near 
its anterior end, its locale is part of the site of 
formation of new buccal organelles during stomato-
genesis ; characteristic of oligohymenophoreans , 
particularly scuticociliates ; a little-used synonym is 
bucco-anal stria (Fig. 2.4D; DM, Fig. 2.7i). 
Discoidal Vesicle : vesicle abundant in the phago-
plasm and involved in building the food vacuole
Dorsal Bristle : see Sensory Bristle . 
Dorsal Brush : see Brosse . 
Dorsal Zone of Membranelles : an older non-
preferred term referring to tufts of syncilia , which 
are not membranelles , located anteriorly and dorsally
on the bodies of many entodiniomorphids . 
Dyad : a paired set or couplet of kinetosomes in 
which the kinetosomal axes are at right angles (per-
pendicular) to the axis of the line or file of the kinetal 
structure of which they are a part; in the case of 
many paroral structures, only the outermost kineto-
some of the dyad is ciliferous ; the term is not used 
for the differently arranged pairs of kinetosomes 
comprising the circumoral ciliature , for which the 
preferred term is oral dikinetid (Fig. 2.1C). 
Ectocommensal : see Commensal . 
Ectocyst : see Cyst . 
Ectoplasmic Flange : see Flange . 
Ectosymbiont ( of Ciliates ): microorganism, such 
as bacteria or other ciliates, attached to the outside 
of the host ciliate; common examples of ciliates as 
hosts include many psammophilic species (e.g., the 
 karyorelictean Kentrophoros ) and commensalistic 
 scuticociliates (e.g., Echinocyclidium ), and ses-
siline peritrichs in which both bell and stalk may 
be involved (e.g., Zoothamnium niveum ). 
Edaphic : in a broad sense, pertaining to all kinds 
of soil, forest litter, and other types of terrestrial 
habitats, including mosses, lichens, and trunks and 
leaves of trees; synonym of terrestrial. 
Elineation : process by which a kinety “divides” or 
separates longitudinally to produce a file of kineto-
somes parallel to itself, increasing the number of 
kineties by one. 
Embryo : see Larval Form . 
Embryo Sac : see Brood Pouch . 
Enantiotropic : a kind of fission typical of oligo-
trichous spirotrichs , said to involve a condition of 
inverse homothetogenic fission and shifting body 
axes via pronounced morphogenetic movements. 
Encystment : the process of cyst formation; see 
Cystation , Excystment . 
Endemic : regularly or only found in a cer-
tain geographic region; see Cosmopolitan and 
Ubiquitous . 
Endocommensal : see Commensal . 
Endogemmy : see Budding and Endogenous 
Budding . 
Endocyst : see Cyst . 
Endogenous Budding : type of single or multiple 
fission taking place within a brood pouch , with the 
embryo or larval form(s) completely free of the 
parental form before emergence through the birth
pore ; characteristic mode of reproduction of certain 
 chonotrichs , where the process is called crypto-
gemmy, and, especially, of certain suctorians (Fig. 
2.11Ca, 2.11Cb). 
Endoplasmic Reticulum (ER) : system of internal 
membranes in the form of flattened cisternae, and/
or vesicles that are related to or derived from the 
Golgi apparatus ; surfaces of the ER membranes 
are sites of ribosomal activity involved in synthesis 
28 2. Glossary of Terms and Concepts Useful in Ciliate Systematics
of secretory proteins, which are then processed by 
the Golgi apparatus. 
Endoral Membrane : see Diplostichomonad , 
Paroral . 
Endoskeletal System : the term preferred by many 
students of the astome oligohymenophoreans (see 
Cytoskeleton ). 
Endosome : somewhat transient, brightly Feulgen-
positive body in the paramere of the heteromerous 
macronucleus of cyrtophorine and chonotrich phyl-
lopharyngeans ; the term is sometimes misused for 
the Feulgen-negative, RNA-containing nucleolus
so commonly found, generally as numerous small 
bodies, in the nucleoplasm of the homomerous 
macronucleus and the orthomere of the heteromer-
ous macronucleus