Answer:
Sympathetic nervous system
Explanation:
The sympathetic nervous system of the autonomic division prepares the body for stress or emergency conditions by generating the “fight-or-flight” responses. The sympathetic nervous system triggers the release of stress hormones from the adrenal medulla to generate the set of physiological responses.
There is dilation of the pupil, and an increased rate of heartbeat and increased blood pressure. Other responses include dilation of airways and dilation of blood vessels that supply blood to skeletal muscles, heart muscles, liver, etc. Under the given emergency condition, the sympathetic nervous system of Meghan was activated to generate the fight or flight response.
Answer:
living organisms are composed of cells.
Organelles cannot survive alone
cells multiply through division
Explanation:
Answer:
b. the bottleneck effect.
Explanation:
The bottleneck effect occurs when a population's size is reduced for at least one generation. This will result in a very reduced genetic variation, which can lead to further adaptation problems.
The Founder effect has its similarities (in terms of the resulting reduced genetic pool) with the bottleneck effect, BUT it occurs when a new colony is started by a few members of the original population.
The Hardy-Weinberg equilibrium is a principle in population genetics that states that the genetic variation in a population will remain constant from one generation to the next IF certain conditions are present (no migration, aleatory mating, among others), so this is not the answer.
Genetic drift (refers to the change in the frequency of an existing gene variant in a population due to random sampling of organisms, so it is not the answer.
A small amount of nitrogen is fixed by lightning, but most of the nitrogen harvested from the atmosphere is removed by nitrogen-fixing bacteria and cyanobacteria (formerly called blue-green algae). The nitrogen cycle transforms diatomic nitrogen gas into ammonium, nitrate, and nitrite compounds.
