Double fertilization in flowering plants requires the delivery of two immotile sperm cells to the female gametes by a pollen tube, which perceives guidance cues, modifies its tip growth direction, and eventually enters the micropyle of the ovule. In spite of the recent progress, so far, little is known about the signaling events in pollen tubes in response to the guidance cues. Here, we show th...

Between 1985 and 1987, fecal samples were collected from 71 bats representing 14 species (Desmodontidae, Molossidae, Noctilionidae, Phyllostomidae, Vespertilionidae) from 8 localities in 3 states (Beni, Pando, Santa Cruz) in Bolivia, South America. Of these, 2 black myotid bats (Vespertilionidae), Myotis nigricans, and 1 tent-making bat (Phyllostomidae), Uroderma magnirostrum, had oocysts in th...

Synbranchus marmoratus (Synbranchidae), commonly known as the swamp eel, is a protogynous diandric teleost fish widely distributed throughout South America. The purpose of this work was to study the ovarian anatomy and to describe oocyte developmental stages in the swamp eel, Synbranchus marmoratus. S. marmoratus has a unique sacular ovary. It is covered by a conspicuous muscular wall, probably...

In the present work, we analyzed the structure of oocytes and fertilized eggs of the piracanjuba fish (Brycon orbignyanus) under light and scanning electron microscopy. After inducing spawning, samples were collected at the moment of oocyte extrusion, when oocytes and semen were mixed (time 0), as well as at 10, 20 and 30 s after mixing, every minute up to 10 min, and then at 15 and 20 min. The...

Fecal samples of 60 turkey poults that showed chronic progressive symptoms like unthriftiness, loss ofweight, diarrhea were collected from the most rural areas with high rate of turkey population in north andwest part of country for intestinal protozoan parasites. According to the morphological characteristics, likeshape, presence or absence of micropyle, and/or polar granule, the 5 different t...

For fertilization to occur in plants, the pollen tube must be guided to enter the ovule via the micropyle. Previous reports have implicated actin filaments, actin binding proteins, and the tip-focused calcium gradient as key contributors to polar growth of pollen tubes; however, the regulation of directional pollen tube growth is largely unknown. We reported previously that Arabidopsis thaliana...

Five parasites are described in the lizard Amphisbaena alba (Amphisbaenidae) from the state of Par , North Brazil. Mature oocysts of Choleoeimeria amphisbaenae n. sp., are passed already mature in the faeces. They are ellipsoidal-cylindrical, average 33.7 x 22.8 m and are devoid of micropyle, oocyst residuum or polar body. The colourless wall is smooth and of 2 layers. The 4 dizoic sporocysts ...

Insect egg micropyles are openings through the chorion allowing sperm entry for fertilisation. Micropyles diverse structures showing remarkable variation in number, spatial arrangement and physical structure across extant insect orders. Despite being almost ubiquitous insects, they have received little attention. As key morphological features of an immobile life stage, it is plausible that part...

Twenty species of bats (Molossidae, Vespertilionidae) were collected from California, New Mexico, Oregon, South Carolina, Utah, and Baja California Norte (Mexico), and 29 of 404 (7%) animals, including Antrozous pallidus, Eptesicus fuscus, Myotis auriculus, Myotis californicus, Myotis ciliolabrum, Myotis evotis, Myotis lucifugus, Myotis thysanodes, Myotis vivesi, Myotis volans, Myotis yumanensi...

fecal samples of 60 turkey poults that showed chronic progressive symptoms like unthriftiness, loss ofweight, diarrhea were collected from the most rural areas with high rate of turkey population in north andwest part of country for intestinal protozoan parasites. according to the morphological characteristics, likeshape, presence or absence of micropyle, and/or polar granule, the 5 different t...