(n.) The hairy or feathery appendage of the achenes of thistles, dandelions, and most other plants of the order Compositae; also, the scales, awns, or bristles which represent the calyx in other plants of the same order.
Example Sentences:
(1) In a series of in virtro experiments (n = 64) using the mature flowers or seeds and pappus hairs of Karoo bushes Chrysocoma ciliata, Dimorphotheca cuneata, Eriocephalus ericoides, Gazania krebsiana and Gnidia polycephala, small phytobezoars were formed from material of E. ericoides, G. krebsiana and G. polycephala either alone or in combinations.
(2) In a small in vivo trial, 4 groups of one sheep and one goat each were fed 10% of either C. ciliata, E. ericoides, G. polycephala seeds and pappus hairs, or a mixture of all 3, added to a basal diet of milled lucerne fed for up to 31 d. Small phytobezoars were formed in the goats but not the sheep receiving C. ciliata, and G. polycephala material.
(3) Of particular interest was the presence of annular thickenings as well as terminal hooks on both bezoar fibres and pappus hairs, both of which structures are believed to be involved in the formation of bezoars.
(4) The chemical composition of bezoars found in goats and sheep, resembled that of pappus hairs and stems of the Karoo bushes Eriocephalus ericoides and Gnidia polycephala more closely than that of mohair.
(5) This close similarity between the fibres in bezoars and those of pappus hairs in the 3 plant species studied, leads to the conclusion that the bezoars consisted largely of pappus hairs of these and possibly other species.
(6) The microscopic structure and ultrastructure of these pappus hairs moreover closely resembled the fibres of bezoars but were quite distinct from that of hair or wool.
(7) These diameters were very similar to those of the pappus hairs surrounding the seeds of the Karoo bushes Chrysocoma ciliata, Eriocephalus ericoides and Gnidia polycephala (means of 6.06 microns, 16.67 microns and 22.73 microns respectively).
Trichome
Definition:
(n.) A hair on the surface of leaf or stem, or any modification of a hair, as a minute scale, or star, or gland. The sporangia of ferns are believed to be of the nature of trichomes.
Example Sentences:
(1) Thus, the genetically conditioned decision of a specific cell to differentiate either a chaeta or a trichome is made during the growth of the wing imaginal disc and is transmitted clonally to descendant cells.
(2) The work shows some distinct differences in trichome morphology as well as variation in their development, due to the effect of indole-3-acetic acid (IAA).
(3) The saturated anacardic acid (C22:0 sat), abundant in the trichome exudate of susceptible strains, was nearly as inhibitory toward both prostaglandin endoperoxide synthase and lipoxygenase as the omega 5-unsaturated compound.
(4) These hormogonia were characterized in terms of their morphology, state of differentiation of the cells, optimal temperature for production and motility, minimal nutritional requirements to sustain motility, liberation of the hormogonium from its parental trichome, average surface velocity, and maximal concentration of agar through which the hormogonium may move.
(5) The characteristics of the growth curve of the organism showed that its growth in shake cultures is by increasing trichome number up to approximately 15 hr and by increasing trichome length after 15 hr.
(6) Illumination of a single cell in the P. uncinatum trichome gives rise to quenching of the fluorescence in this cell and usually in one or two neighbor cells, whereas the rest of trichome remains fluorescing.
(7) Also, this species shows more specialized foliar trichomes which permit the uptake of water and possibly of nutrients.
(8) Previously, we reported that hapten-immune animals showed increased collagen deposition as identified on routine paraffin fixed slides that were stained with Masson's trichome.
(9) The source of the epidemic are the strong sensitizing sesquiterpene lactones parthenin, ambrosin and others, which are highly concentrated in the trichomes of the plant.
(10) changed morphology from rods of about 6 to 8 microns long to multicellular filaments (unsheathed trichomes) up to many hundreds of micrometres long with the addition of glycine or certain D-amino acids to the growth medium.
(11) The putative GL1 promoter directs the expression of the GUS reporter gene in non-trichome-bearing structures that appear to be stipules.
(12) Histochemical localization of the reporter gene product suggests that the as-2 tetramer directs expression in trichomes, vascular elements, and epidermal and mesophyll cells.
(13) It is concluded ethylrhodamine can be used to monitor the power transmission which was previously demonstrated by microelectrode studies of the cyanobacterial trichomes.
(14) The construction of cell hairs (trichomes) on the wings of Drosophila occurs in synchrony on 30,000 cells over a period of about 20 hr.
(15) Haematoxylin and Eosin, Masson's Trichome, and high iron diamine Alcian blue staining was done in all the cases.
(16) A scanning electron microscopic study of trichome morphology of bean embryo, growing in semi-solid synthetic medium, has been undertaken.
(17) In young expanding leaves, P2 protein is concentrated in palisade cells and in epidermal trichomes.
(18) In certain trichomes, several "dark" cells appear during the storage of the trichomes without energy sources.
(19) The GL1 gene is required for the initiation of differentiation of hair cells (trichomes) on the crucifer, Arabidopsis thaliana.
(20) Very similar inhibition was seen with the crude exudate, rich in omega 5-anacardic acids, from glandular trichomes of an arthropod-resistant strain of geranium, Pelargonium xhortorum.