Answer:
<u>Antigenic drift</u> refers to the slow accumulation of genetic changes to an influenza virus over time.
Explanation:
Antigenic drift is defined as the mechanism by which viruses undergo variation. This mechanism involves the slow accumulation of mutations in the viral genes, that are responsible for coding the antibody binding sites. This leads to the formation of a new strain of virus, which can't be inhibited by the old antibodies. Due to this, the virus can easily spread the disease.
The antigenic drift occurs in the influenza A virus and also the influenza B viruses.
Therefore, <u>Antigenic drift refers to the slow accumulation of genetic changes to an influenza virus over time.</u>
Average annual precipitation and temperature.
increase because of carbon
Answer:
The correct answer would be A. crust.
The crust is the outermost layer of the earth which is composed of different types of rocks such as sedimentary, metamorphic, and igneous rocks.
It is completely solid and can be broadly classified into two types: continental crust and oceanic crust.
The thickness of the oceanic crust is about 5 km to 10 km. It is primarily composed of basalt, gabbro, and diabase.
The thickness of the continental crust is around 30 km to 50 km.
The crust forms lithosphere along with hard and upper mantle.
We live long lives compared to a lot of animals, we are at the top of the food chain, we are omnivores and have a larger variety of foods we can eat that’ll nurture our bodies
