نتایج جستجو برای: sperm biology

تعداد نتایج: 198940  

2016
Aaron Teo James R. Guest Mei Lin Neo Kareen Vicentuan Peter A. Todd

Most studies of coral reproductive biology to date have focused on oocyte numbers and sizes. Only one (ex situ) study has enumerated sperm numbers, even though these data have multiple potential applications. We quantified total coral sperm and eggs per gamete bundle collected from six species in situ during a synchronous spawning event in Singapore. Egg-sperm bundles were captured midwater as ...

Journal: :فلسفه 0
paul griffiths

the philosophy of biology has existed as a distinct sub-discipline within the philosophy of science for about thirty years. the rapid growth of the field has mirrored that of the biological sciences in the same period. today the discipline is well represented in the leading journals in philosophy of science, as well as in several specialist journals. there have been two generations of textbooks...

Journal: :Biology of reproduction 1998
T T Smith

During their sojourn in the female tract, sperm come into contact with the epithelial cells that line the tract and their secretions. In the past, much attention has been given to the nature and composition of uterine and oviductal fluid [1-3] with the aim of understanding what components of these fluids may affect the events associated with fertilization and preimplantation embryo development....

Journal: :Genome 2004
S Kirankumar T J Pandian

Interspecific androgenetic rosy barb (Puntius conchonius) was generated using its cadaveric (-20 degrees C) or fresh sperm to activate nuclear genome inactivated oocytes of gray tiger barb (Puntius tetrazona). UV irradiation was used to inactivate nuclear genome of tiger barb oocytes. Thermal shock restored diploidy of rosy barb in the oocytes of tiger barb. Survival of androgenotes was 14% or ...

Journal: :Journal of andrology 2008
Terry T Turner

The epididymis consists of a single, highly coiled and convoluted tubule that Antoine De Graaf, the famous 17th-century anatomist, likened to a thread thickening to a string. The uncoiled tubule is several meters long and sperm in transit through it become functionally mature under the under the influence of the tubule lumen's microenvironment. The regulation of that microenvironment and the ma...

Journal: :Annual review of cell and developmental biology 2002
Elizabeth M Lord Scott D Russell

In flowering plants, pollen grains germinate to form pollen tubes that transport male gametes (sperm cells) to the egg cell in the embryo sac during sexual reproduction. Pollen tube biology is complex, presenting parallels with axon guidance and moving cell systems in animals. Pollen tube cells elongate on an active extracellular matrix in the style, ultimately guided by stylar and embryo sac s...

2017
Leah Springate Timothy R Frasier

Fertilization represents a critical stage in biology, where successful alleles of a previous generation are shuffled into new arrangements and subjected to the forces of selection in the next generation. Although much research has been conducted on how variation in morphological and behavioural traits lead to variation in fertilization patterns, surprisingly little is known about fertilization ...

Journal: :journal of reproduction and infertility 0

some cases of male infertility are due to the destructive side-effects of anticancer treatment methods such as chemo and radiotherapies on germ cell lines. the increase in the survival rate of cancer patients who undergo treatment, especially children, has drawn attention to fertility preservation. the most common and effective technique in preserving male fertility is sperm freezing and its su...

Journal: :Asian journal of andrology 2011
R John Aitken Ralf R Henkel

M ajor advances in biomolecular techniques as well as in the sensitivity and accuracy of mass spectrometers are transforming the scientific landscape by fueling unprecedented advances in analytical biochemistry—the ’omics revolution, which refers to the study of genes (genomics), transcripts (transcriptomics), proteins (proteomics) and the various metabolites (metabolomics). It is now possible ...

2016
Anke Reinders

Pollen, the male gametophyte (haploid generation) of flowering plants, is responsible for delivering sperm cells to the egg sac, a process essential for sexual reproduction. Interaction between pollen and stigma (pollination) initiates secretion in the stigma and pollen germination. The pollen tube emerges and grows through the style to the ovaries where it delivers the sperm cells to the ovule...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید