What percent of potassium-40 remains undecayed in a rock that is 3.9 billion years old? The 3.9 billion year old rock has undergone three half-lives (3.9 divided by 1.3 = 3). After 3 half-lives, 12.5% of the potassium-40 remains undecayed.
Sometimes genes change their form in a process without a reason and it's called spontaneous mutation. Spontaneous mutations<span> occur with non-zero probability. And they occur even in an uncontaminated cell. They are characterized by the specific changes.</span>
Answer:
They are intermediate hosts.
Explanation:
Disease-transmitting insects are called vectors.
The life cycle of disease-causing pathogens is closely linked to the biology of the insect that carries it.
The symptoms of gongylonemiasis include hemorrhagic inflammation at the site the pathogen invades, followed by granulomatous tissue development that produces nodules in the invaded organ.
Some diseases transmitted by insects occur in both humans and other mammals because our differences in anatomy and physiology are not very different.
It is unlikely that clinical symptoms will occur in humans if the insect were the definitive host, because our biology is quite different from their biology, and the pathogen would be adapted to fulfill its entire life cycle in their body.
