A simple difference in the body design of two species of marine urochordates in the ascidian genus Corella suggested that these species may differ in their mating systems. The two coexisting species share common life-history traits and morphology with the exception of a difference in body design that affects site of fertilization and embryonic development. Corella inflata has internal fertiliza...

Male subfertility/infertility is acknowledged to contribute significantly to infertility problems experienced by couples. In some instances, morphological and/or physiological defects known to interfere with normal sperm function can be identified. However, in others, no obvious cause of fertilization failure can be identified. The recent introduction of molecular methods has made it possible t...

Centrifugal countercurrent distribution (CCCD) in an aqueous two-phase system (TPS) is a resolute technique revealing sperm heterogeneity and for the estimation of the fertilizing potential of a given semen sample. However, separated sperm subpopulations have never been tested for their fertilizing ability yet. Here, we have compared sperm quality parameters and the fertilizing ability of sperm...

sperm is produced by the testis and mature in the epididymis. for having a successful conception, the fertilizing sperm should have functional competent membranes, intact acrosome, functional mitochondria and an intact haploid genome. the effects of genetic and environmental factors result in sperm vulnerability to damage in the process of spermatogenesis and maturation. in recent years, the fe...

Fertilization promoting peptide (FPP), structurally similar to thyrotrophin releasing hormone, is produced by the prostate gland and secreted into seminal plasma. Recent in vitro studies have provided evidence that FPP elicits biologically relevant responses in mouse, human and boar spermatozoa. In the presence of nanomolar concentrations of FPP, spermatozoa become fertilizing more quickly and ...

Self?fertilization commonly occurs in hermaphroditic species, either occasionally or as the main reproductive mode. It strongly affects genetic functioning of a population by increasing homozygosity and drift reducing effectiveness recombination. Balancing selection is form that maintains polymorphism, which has been extensively studied outcrossing species. Yet, despite recent developments, ana...