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.
MRNA is needed in the cells because it directs the synthesis of proteins which is found in the cytoplasm. It is a molecule that carries the message contained within DNA to the ribosome. The Proteins are assembled on the ribosomes using the mRNA nucleotide sequence as a guide.
Answer:
During crossing over, part of one chromosome is exchanged with another. The result is a hybrid chromosome with a unique pattern of genetic material. Gametes gain the ability to be genetically different from their neighboring gametes after crossing over occurs.
This can cause mutations, these mutations can be helpful,harmless or they can be harmful.