scholarly journals Waltomyces, a new ascosporogenous yeast genus for the Q10-equipped, slime-producing organisms whose asexual reproduction is by multilateral budding and whose ascospores have smooth surfaces.

1985 ◽  
Vol 31 (5) ◽  
pp. 491-492 ◽  
Author(s):  
YUZO YAMADA ◽  
TAKASHI NAKASE
Keyword(s):  
Asexual Reproduction ◽  
Smooth Surfaces ◽  
Yeast Genus ◽  
Ascosporogenous Yeast

The coenzyme Q system in the classification of the ascosporogenous yeast genus Dekkera and the asporogenous yeast genus Brettanomyces

1980 ◽  
Vol 46 (6) ◽  
pp. 595-599 ◽  
Author(s):  
Y. Yamada ◽  
Hisano Takinami-Nakamura ◽  
Y. Tahara ◽  
Maudy Th. Smith
Keyword(s):  
Coenzyme Q ◽  
Yeast Genus ◽  
Ascosporogenous Yeast ◽  
Q System

Stereo Electron Microscopy Applied to High Resolution Freeze-Etch Replicas

1970 ◽  
Vol 28 ◽  
pp. 306-307
Author(s):  
L. Andrew Staehelin
Keyword(s):  
Electron Microscopy ◽  
Plastic Deformation ◽  
High Resolution ◽  
Smooth Surfaces ◽  
Small Particles ◽  
Membrane Surfaces ◽  
Wide Acceptance ◽  
New Information ◽  
Number Of Particles ◽  
Small Holes

Freeze-etched membranes usually appear as relatively smooth surfaces covered with numerous small particles and a few small holes (Fig. 1). In 1966 Branton (1“) suggested that these surfaces represent split inner mem¬brane faces and not true external membrane surfaces. His theory has now gained wide acceptance partly due to new information obtained from double replicas of freeze-cleaved specimens (2,3) and from freeze-etch experi¬ments with surface labeled membranes (4). While theses studies have fur¬ther substantiated the basic idea of membrane splitting and have shown clearly which membrane faces are complementary to each other, they have left the question open, why the replicated membrane faces usually exhibit con¬siderably fewer holes than particles. According to Branton's theory the number of holes should on the average equal the number of particles. The absence of these holes can be explained in either of two ways: a) it is possible that no holes are formed during the cleaving process e.g. due to plastic deformation (5); b) holes may arise during the cleaving process but remain undetected because of inadequate replication and microscope techniques.

Ultrathin Insulator Films with Atomically Smooth Surfaces Using Plasma Processing

2008 ◽  
Author(s):  
Venkateswara Bommisetty ◽  
Rojan L. Karmacharya ◽  
Suravi Shrestha ◽  
David Galipeau
Keyword(s):  
Plasma Processing ◽  
Smooth Surfaces

Gemmae in Tetralophozia setiformis (Anastrophyllaceae, Marchantiophyta) and their second record in Eurasia

2017 ◽  
Vol 51 ◽  
pp. 242-250
Author(s):  
M. V. Dulin
Keyword(s):  
British Columbia ◽  
Asexual Reproduction ◽  
Leaf Shape ◽  
Leaf Size ◽  
Komi Republic ◽  
The Other ◽  
Widespread Species ◽  
Northern Urals ◽  
Sexual And Asexual Reproduction ◽  
Murmansk Region

Tetralophozia setiformis is a widespread species occurring usually without organs of sexual and asexual reproduction. Gemmae of Tetralophozia setiformis were observed for the second time in Russia and Eurasia in the Northern Urals, Komi Republic. They form compact masses over upper leaves. The compact masses consist largely (70 %) of immature gemmae. Description of gemmae and gemmiparous shoots from the Northern Urals and their comparison with those from the other known localities, namely British Columbia (Canada) and the Murmansk Region (European Russia) were carried out. The gemmiparous plants of T. setiformis from the Northern Urals have approximately the same width as plants without gemmae but they are shorter. The leaves of gemmiparous plants from the Northern Urals are similar to leaves of gemmiparous plants from British Columbia. The leaf shape in upper part of the gemmiparous shoots varies from the typical to ± modified from gemmae production. These leaf shape transitions include reduction of leaf size and lobe number from 4 to 2–3, suppression of development and disappearance of characteristic teeth at the base of sinus. Gemmae size (17 × 22 μm) of plants from the Northern Urals is within variability recorded for plants from the Murmansk Region and British Columbia.

Molecular basis of adaptive evolution of sperm motility involved in in vivo fertilization of terrestrial animals

Impact ◽  
2020 ◽  
Vol 2020 (6) ◽  
pp. 73-75
Author(s):  
Akihiko Watanabe
Keyword(s):  
Sexual Reproduction ◽  
Sperm Motility ◽  
Asexual Reproduction ◽  
Acrosome Reaction ◽  
Sperm Morphology ◽  
Adaptive Potential ◽  
Selective Pressures ◽  
The Face ◽  
Genetic Profiles

One of the unifying traits of life on this planet is reproduction, or life's ability to make copies of itself. The mode of reproduction has evolved over time, having almost certainly begun with simple asexual reproduction when the ancestral single celled organism divided into two. Since these beginnings' life has tried out numerous strategies, and perhaps one of the most important and successful has been sexual reproduction. This form of reproduction relies on the union of gametes, otherwise known as sperm and egg. Evolutionarily, sexual reproduction allows for greater adaptive potential because the genes of two unique individuals have a chance to recombine and mix in order to produce a new individual. Unlike asexual reproduction which produces genetically-identical clones of the parent individual, sex produces offspring with novel genes and combinations of genes. Therefore, in the face of new selective pressures there is a higher chance that one of these novel genetic profiles will produce an adaptation that is advantageous in the new circumstances. Dr Akihiko Watanabe is a reproductive biologist based in the Department of Biology, Faculty of Science Yamagata University in Japan, he is currently working on three research projects; a comparative study on the signalling pathways for inducing sperm motility and acrosome reaction in amphibians, the mechanism behind the adaptive modification of sperm morphology and motility, and the origin of sperm motility initiating substance (SMIS).

Sign in / Sign up

Export Citation Format

Share Document