DNA is a negatively-charged molecule. Also cell membranes are negatively charged. The problem would be how to push this charges together? I<span>f you put some CaCl2 into the mixture, the CaCl2 will "split" giving 2Cl- and Ca2+. This last ion will be attracted by the negatively charged DNA and will "cover" it, hiding its negative charge. Hope this answers the question.</span>
i believe the answer is "A fundamental role". hope this helps.
Answer:
Environmental factors can influence natural selection because they can increase or decrease the amount of genetic variation in a population.
Explanation:
Natural selection is a process that involves the survival of species through changes in the expression of their genes, making possible the process of adaptation to environmental changes. It is one of the explanations for the biological evolution of species.
The second premise, necessary for natural selection to be possible, implies the existence of a variability (genetics) of traits among individuals in a population.
The other premises of natural selection are the faculty of traits to be inheritable and that genetic variability should lead to reproductive success and survival.
- <em>The other options are not related to the process of natural selection, since it is not possible for natural selection to increase or decrease the number of chromosomes, in addition to the fact that genetic variability must be observed in a population, not in a single individual, to be considered natural selection </em>
The answer is an average couple is fertile for only 6-7 days. If a couple cannot produce healthy sperm and egg there are the various treatment to help infertile couples to become pregnant and can have their own child. Infertility happens if there is the failure to conceive consecutive 12 months despite the attempts.
