Having the occasional alcoholic drink is unlikely to affect your fertility. But heavy drinking and smoking can reduce sperm quality, lower testosterone production, and make it harder to achieve an erection. It can also lead to liver damage, which affects both your general and reproductive health
<span>In bacteria, DNA polymerase adds an incorrect base to a growing strand of DNA about once in every 100 000 bases added. The result is a mismatch such as the pairing of A with C.
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There is much more fresh water underground than on the surface. A rock layer must be porous and permeable to be a good aquifer. An impermeable layer makes up the bottom of an aquifer. The water table rises and falls with additions or subtractions to the groundwater system.
Sexual intercourse. The developing of the female egg cells and the production of sperm cells