Most sperm cells die in the vagina when entering the female's body because Most sperm cells die in the vagina when entering the
female's body because - the female's reproductive tract is protected by digestive enzymes.
- the sperm cannot pass through the mucus.
- macrophages from the female's immune system destroy all nonself cells.
- of the low pH of the vagina.
- the sperm cells have not yet been activated to swim.
The pH of the vagina is maintained at highly acidic levels to prevent the germ buildup. The range of vaginal pH is around 3.8 to 4.5. The very low pH of the vagina creates a hostile environment for sperms and most of the sperms are killed as they enter the vagina due to the acidic pH.
Apart from supplementing the sperms with energy, cervical mucus serves to protect the sperms from the hostile conditions of the vagina. The cervical mucus has an alkaline pH at or near the ovulation to protect sperms from acidic pH of the vagina and to facilitate fertilization.
The term used to describe an organic cofactor is that this common chemistry allow cells to use a small set of metabolic intermediates to carry chemical groups between different reactions. These group-transfer intermediates are the loosenly-bound organic cofactors, often called coenzymes.
In natural selection process of evolution, traits that are essential for an individual to be fit enough to survive under environmental stress become dominant.
Since the flowers are of blue or yellow color, it is essential for a bee to be able enough to perceive the blue and yellow color. Hence, the eyes of bee with time have evolved to perceive these two color so that they can pollinate flower.
