Overproduction is a natural phenomenon in which the number of produced offspring is higher than the number of individuals the ecosystem can sustain. Thus, competition for limited resources occurs.
Because of the genetic variation, the organisms within a population have different chances to reproduce. Most often, some organisms have a lower reproductive success than others do.
The number of individuals with a high reproductive success is rather low as few males are very successful at passing on their genetic material.
The number of organisms with no reproductive success is also very low, as these "ill adapted" individuals will disappear from the population extremely quickly.
Genetic variation is the amount of differences between individuals. Thus, no organism taken by itself has any genetic variation.
Answer:
Idealized pyramid of net production uses the typical values of 1% for the conversion of sunlight energy to net primary production and 10% for trophic efficiency.
Explanation:
in real ecosystems, trophic efficiencies usually vary from about 5% to about 20%. As a result, net production diagrams for ecosystems have a pyramid shape. Two key factors explain why trophic efficiencies are relatively low, and thus why net production diagrams are shaped like pyramids. First, not all the organisms at one trophic level are eaten by organisms at the next trophic level. For example, not every plant is eaten by herbivores, and not every herbivore is eaten by carnivores. Second, because of the bioenergetics of animals, not all the food an animal eats is converted to new biomass. Significant amounts of energy are lost in feces, used in cellular respiration, and lost to the environment as heat.
Answer:
C.
Explanation:
Nitrogen fixation is a process by which molecular nitrogen in the air is converted into ammonia or related nitrogenous compounds in soil. Atmospheric nitrogen is molecular dinitrogen, a relatively nonreactive molecule that is metabolically useless to all but a few microorganisms.
Answer:
Fossils are formed through preservation: Freezing.
Explanation:
Ice and low temperatures keep organisms from decaying. Large mammals have been found buried in ice, probably caused by earthquakes and avalanches, in Siberia and Alaska.