The answer is D.
With mechanical advantage, less work is put in for a better result.
It can apply force in a shorter distance, but increase distance itself.
Answer:
The process where organisms naturally go and adapt to enviroment where they can most likely survive and produce more offspring.
Explanation:
Theory was first made by Charles Darwin and is now believed to be the main process that brings about evolution.
The situation is an example of negative reinforcement.
In the condition of negative reinforcement, a stimulus especially an unpleasant stimulus is removed due to a particular behavior of the person. In this case, the unpleasant behavior is the headache, and taking aspirin is a behavior of Nancy, which cut of the stimuli, that is pain relieving. In negative reinforcement a particular behavior is increased, in order to remove the unpleasant stimulus.
Answer:
Mutations leading to the better attachement of virus to the host cell would allow the virus to spread the infection and leave more progeny. The reproductive fitness of mutant viruses would allow the mutation to spread.
Explanation:
1. The organisms with same resource requirement compete with each other. Viruses are not living things but once inside the host cell, they behave like living things. Rapid multiplication of virus overpopulate the host cells.
2. Genetic variations are added to the viral progeny by random errors during replication of the viral genome. These random variations may impart beneficial trait, harmful feature or remain neutral. If a random mutation in the SARS-CoV2 virus allows it to adhere better to the cells of the respiratory system, the virus would be better able to infect these cells to spread the infection. Once inside the host cells, the mutant virus would leave more progeny. On the other hand, the wild type virus that lack this mutation would have lesser chances of entering the host cells and may or may not replicate.
3. The progeny of the mutant virus would compete better with the non mutant ones due to the presence of same mutation.
4. Differential reproduction and more progeny of the mutant virus would spread the mutation among the virus.
