(1) The coral-reef fish Anthias squamipinnis is a protogynous hermaphrodite in which all individuals mature initially as females.
(2) We investigated the role of 11-ketotestosterone (11KT) and testosterone (T) in the regulation of territorial behavior in a wild population of a protogynous reef fish, the stoplight parrotfish, at Glover's Reef, Belize.
(3) In spite of this plasticity, the primacy of female development is suggested by the initial ovarian phase in the development of gonads of both sexes in some gonochoristic fishes and by protogynous sex change.
(4) Sex inversion of Epinephelus microdon, a protogynous hermaphrodite was studied using light and electron microscopic criteria.
(5) The plasma levels of both the free and conjugated forms of six sex steroids (androstenedione, testosterone, 11-oxotestosterone, 11 beta-hydroxytestosterone, estrone, and 17 beta-estradiol) were determined by radioimmunoassay combined with Celite chromatography in different sexual phases of the protogynous Monopterus albus throughout the reproductive cycle.
(6) We studied DNA from the protogynous sex-changing fish Anthias squamipinnis to evaluate the recent observation that male-specific bands are identified after hybridization with Bkm, a probe originating in the W chromosome of the snake Bungarus fasciatus.
(7) A fish (Sparidae) Spondyliosoma cantharus L. has been chosen because of his protogynous hermaphroditism.
(8) 3 protogynous hermaphrodites were found in a domesticated strain of Xiphophorus helleri, confirming much doubted observations by older authors.
(9) T. b. brevipalpis is exceptional among mosquitoes in being protogynous at emergence, although it is not protogynous at pupation: the earlier emergence of females reflects the shorter duration of their pupal stage.
(10) In the protogynous stoplight parrotfish (Sparisoma viride), large males defend territories that encompass the home-ranges of several mature females.
(11) Serum levels of 17 beta-hydroxy-4-androstene-3,11-dione (11-KT) and testosterone in the protogynous black sea bass, Centropristis striatus fluctuate annually, correlated with the breeding season.
(12) Large and small males of the protogynous wrasse, Thalassoma duperrey differ in reproductive behavior, gonad morphology, and gonadal steroid production.
(13) Many patterns will be available; one suggested here is of protogynous hermaphroditism, i.e.
(14) We studied a protogynous hermaphrodite, Coris julis, in order to examine whether the change of a female to a secondary male also involves a change in the Sxs-antigen phenotype.
Spermatozoid
Definition:
(n.) The male germ cell in animals and plants, the essential element in fertilization; a microscopic animalcule-like particle, usually provided with one or more cilia by which it is capable of active motion. In animals, the familiar type is that of a small, more or less ovoid head, with a delicate threadlike cilium, or tail. Called also spermatozoon. In plants the more usual term is antherozoid.
Example Sentences:
(1) The spermatozoid content of DNA was analyzed using the Feulgen staining method and the relative content of histone proteins by the Alfert and Geschwind staining method.
(2) The presence of antibodies against spermatozoids was considered as an important factor associated with AIDS and previous states of the AIDS detected by OKT8 greater than 30% of lymphocytes.
(3) The authors analyzed in 196 sterile women the ovulation mucus by the microagglutination test and found a high anti-spermatozoidal activity in 24 (12%) women.
(4) The predominant cytologic features were granulomatous inflammation (nontuberculous and non-foreign body) and spermatozoids (intrahistiocytic or as extracellular spermatic debris).
(5) The Hynie method was observed to have some advantages over other methods: it is easy to apply and provides exact data which are useful in determining spermatozoidal deficiencies in sterility cases.
(6) In animals of both subgroups the spermatozoid concentration in the epididymal suspension was lowered and the relative content of spermatozoids with morphologically abnormal heads in suspension smears was increased.
(7) The microtubules on the outside of the nucleus of the mature spermatozoid of Pteridium form a complex with the envelope, and the perinuclear space is eliminated.
(8) A relationship between transferrin and spermatozoid concentration in sperm was shown.
(9) This membrane also undergoes growth, the outer layer extending into the cytoplasm and surrounding spermatozoid mitochondria.
(10) This layer may be important in preventing other spermatozoids from fusing with the egg.
(11) Similarly, the incubation of spermatozoids obtained from the tail of the epididymis with CPhM causes them to produce only 7% fertilization, instead of the normal rate of 80%.
(12) The prognosis depends on the alterations seen on the sperm count parameters; but there is no threshold figure under which no pregnancy is observed (except for zero), concerning the count, the gradual mobility or the morphology of the spermatozoids.
(13) The quantitative yield is given for DNA and RNA preparations from the mentioned objects, the molecular weight of roach and bream DNA, nucleotide composition of roach DNA as well as fractional composition of bream spermatozoids RNA are determined.
(14) The ultrastructure of the mature spermatozoid of Marsilea vestita was studied after its release from the microspore and prior to its penetration of the egg.
(15) After spermatozoid penetration, a new extracellular layer appears above the surface of the egg, beginning in the region of sperm penetration and spreading across the top of the egg.
(16) Changes in the nucleus and the cytoplasm of both the spermatozoids and spermatides were revealed at the early stages of their formation.
(17) Circadian rhythm of activity of 3H-leucine incorporation into antheridial cells of Chara vulgaris, in natural photoperiod was compared with changes in mitotic activity of antheridial filament cells which form spermatozoids.
(18) Any abnormality often severely compromises the ability to fertilize spermatozoids.
(19) The various criteria of the sperm count then examined, emphasizing the importance of studying the morphology, on optical as well as electron microscopy, since it is the spermatozoid's morphology as well as their mobility that differentiate fertile man from infertile ones.
(20) is fertilized by small biflagellate spermatozoids and both monoecious and dioecious species are found.