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Sperm motility describes the ability of sperm to move properly through the female reproductive tract (internal fertilization) or through water (external fertilization) to reach the egg. Sperm motility can also be thought of as the quality , which is a factor in successful conception ; sperm that do not "swim" properly will not reach the egg in ...
Hyperactivation is a type of sperm motility.Hyperactivated sperm motility is characterised by a high amplitude, asymmetrical beating pattern of the sperm tail ().This type of motility may aid in sperm penetration of the zona pellucida, which encloses the ovum.
The ability of the males to over-power the females' original mate choice resulted in the offspring of the targets of male aggression having low genetic diversity. Offspring with high genetic diversity seemed to happen only when the operational sex ratio was female-biased, when females were more likely to be able to exert mate choice, and males ...
An influx of Ca 2+ produces increased intracellular cAMP levels and thus, an increase in motility. Hyperactivation coincides with the onset of capacitation and is the result of the increased Ca 2+ levels. It has a synergistic stimulatory effect with adenosine that increases adenylyl cyclase activity in the sperm. [citation needed]
A 1992 World Health Organization report described normal human semen as having a volume of 2 mL or greater, pH of 7.2 to 8.0, sperm concentration of 20×10 6 spermatozoa/mL or more, sperm count of 40×10 6 spermatozoa per ejaculate or more, and motility of 50% or more with forward progression (categories a and b) of 25% or more with rapid ...
External fertilization is a mode of reproduction in which a male organism's sperm fertilizes a female organism's egg outside of the female's body. [1] It is contrasted with internal fertilization, in which sperm are introduced via insemination and then combine with an egg inside the body of a female organism.
These differences are caused by the effects of the different sex chromosome complement in males and females, and differential exposure to gonadal sex hormones during development. Sexual dimorphism is a term for the phenotypic difference between males and females of the same species.
Sperm quantity and quality are the main parameters in semen quality, which is a measure of the ability of semen to accomplish fertilization. Thus, in humans, it is a measure of fertility in a man. The genetic quality of sperm, as well as its volume and motility, all typically decrease with age. [17]