Answer:
Option A, oxygen in the atmosphere
Explanation:
The highest level of oxygen reached during this phase of the geological cycle of earth. The oxygen level in Carboniferous period accounted for 35% as compared to 21% of oxygen in the atmosphere in present time.
Due to high oxygen content, the giant and wide varieties of terrestrial animal and plant species evolved. For example – size of insects and carwlies increased, plant became extremely giant, increase in number of tree ferns etc.
Answer:
The correct answer is - B. It introduces new alleles into a population.
Explanation:
Gebe flow or migration is the transfer of the genetic material or transfer of genes from one population to another population of the same species. Gene flow is also responsible for the genetic change that leads to evolution.
Gene flow can contribute in various ways such as migration or vertical gene transfer parent to progeny, however, it can lead to evolution directly by introducing new alleles into a population.
Answer:
the average percentage of energy lost as heat
Explanation:
An energy pyramid (also called trophic pyramid) is a graphical representation that exhibits how energy flows at each trophic level in a particular ecosystem. In an energy pyramid, it is possible to determine how much energy is available at each trophic level and how energy flows from producers (e.g., photosynthetic plants) to primary consumers (e.g., herbivores), then from primary consumers to the next trophic level (e.g., carnivores), and so successively to all major trophic groups (e.g., higher carnivores). During this chain, energy is lost as heat when it is transferred to the next level, and the average percentage of energy lost increases at each trophic level, thereby less and less energy is available to major trophic groups.
