Oral polio vaccine is highly effective and inexpensive (about US$0.10 per dose, or US$0.30 per child and its availability has bolstered efforts to eradicate polio. A study carried out in an isolated Eskimo village showed that antibodies produced from subclinical wild virus infection persisted for at least 40 years. Because the immune response to oral polio vaccine is very similar to natural polio infection, it is expected that oral polio vaccination provides similar lifelong immunity to the virus.
Contact immunity to polio can occur when attenuated poliovirus derived from the oral polio vaccine is excreted, and infects and indirectly vaccinates unvaccinated individuals.
Answer:Enzymes are biological catalysts. Catalysts lower the activation energy for reactions. The lower the activation energy for a reaction, the faster the rate. So enzymes speed up reactions by lowering activation energy
Answer:
A monohybrid cross is defined as the cross happening in the F1 generation offspring of parents differing in one trait only. A dihybrid cross is a cross happens F1 generation offspring of differing in two traits.
Explanation:
and the tow words have a prefix and mono means one and the dihy means two. a hydrate containing two molecules of water.
B. Hydrogen bonds make the positive sides of water molecules stick to each other
Answer: Located within the thermosphere, the ionosphere is made of electrically charged gas particles (ionized). The ionosphere extends from 37 to 190 miles (60-300 km) above the earth's surface. It is divided into three regions or layers; the F-Region, E-Layer, and D-Layer.
Explanation: