Viruses can multiply very quickly, and so they can go through natural selection at a much quicker rate, allowing certain vaccine resistant mutations to take over a population.
Answer:
A rule Anatomists follow to name the muscles is to name them after a description of the muscle in some way. These include naming the muscle after its shape, its size compared to other muscles in the area, its location in the body
Explanation:
Some examples are flexor (decreases the angle at the joint), extensor (increases the angle at the joint), abductor (moves the bone away from the midline), or adductor (moves the bone toward the midline).
Diatoms
http://ugf3g1.rg.ro/Y4-3
This may help you props to the owner of this pdf
Pretty sure its the same way a egg is fertilized.