The right answer is B.
Cholera vaccination is only recommended for staff who have to intervene with patients in an epidemic situation. In all other cases, effective prevention is provided by good personal hygiene (washing hands) and food.
It is also important to know that this vaccine does not protect permanently: It protects only about 90% within 6 months, then to 50% within 3 years.
Answer:
The correct answer is -
A) BbTt x bbTt
B) .5^4 or 1/16 or 0.0625
Explanation:
As it is given that Brachydactylus and PTC tasters both traits are autosomal dominant conditions which mean only one allele would be enough.
For Branchydactylus and For tasting : man and women will be heterogeneous.
Hence,
The Genotype of man = BbTt
The Genotype of wife = bbTt
b. Answer = 0.0625
For Branchydactylus:
Bb X bb
Possible genotypes:
B b
b Bb( Brachydactylus) bb(normal)
b Bb (Brachydactylus) bb (normal)
The probability of a single child being Branchydactylus = 2/4 = 0.5
So, Probability of all 4 child being Branchydactylus = .5 x .5 x .5 x .5 = 0.0625
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.