The answer is; D.
This can be called a secondary ecological succession because it includes the disruption of the former ecology, rather than the ecological succession from a new environment-primary succession. The invasive species outcompete the native species in their environment. In addition, the invasive species lack a natural predator hence spread unregulated in the environment.
Answer:
C) In 1946, the Argentinian government imported fifty beavers from Canada, which were to be released in Cami Lake with the intention of creating a commercial fur trading industry. Though a viable industry ultimately failed to materialize, the introduction of the beavers into the region has had far-reaching consequences.
B) Embryonic stem cell research requires the use of human embryos. Its an unethical dilemma.
Motor unit refers to the functional element of muscle contraction during an exertion. There are two basic types of motor unit: large and small motor units. During low to moderate level exercise, small motor units are activated. Small motor units are recruited during sustained activity; is made up of high proportion of type 1 muscle fibers, which are resistant to fatigue