Answer:
Perder un testículo usualmente no tiene ningún efecto en la capacidad de un hombre de lograr una erección y tener sexo. No obstante, si se extirpan ambos testículos, no se pueden producir espermatozoides y el hombre queda estéril.
Explanation:
What is this for is it biology
Answer:
The correct answer is diaphragm.
Explanation:
One of the barrier methods of controlling birth is the diaphragm. It is abstemiously efficient, with a one-year failure rate of approximately 12 percent with the typical application. It is positioned over the cervix with spermicide prior to having sex and is left in position for about 6 hours post-sex.
It is a rubber barrier that holds the spermicide against the cervix. The spring in the diaphragm's rim produces a seal against the walls of the vagina. The diaphragm covers the cervix and physically inhibits sperm from getting inside the uterus via the internal orifice of the uterus. Basically, the diaphragm has an application with spermicide, and it is broadly considered that the spermicide substantially enhances the efficacy of the diaphragm.
Flu vaccines need to be revised and changed every year because the flu virus constantly mutates. Flu viruses can change in two ways: drift or shift. Antigenic drift occurs when genes of the virus slowly change during replication until the immune system no longer recognizes it. On the other hand, antigenic shift occurs when a major change in the virus happens. This usually leads to a totally different kind of virus. This is what happened during the H1N1 scare in 2009.
DNA viruses like mumps are less prone to mutation due to the presence of DNA polymerase. RNA viruses are more prone to mutation because they undergo reverse transcription to simulate the role of DNA.
Directional selection acts against b<span>oth extremes simultaneously in the variation of the trait. This is the most "aggressive" form of selection and only happens in extreme areas.
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