Answer:
Extrinsic regulatory mechanisms are external and depend on the firing of some factor outside the population itself. Among them are interspecific competition, food and space restrictions, very strong climatic variations, weathering and inharmonious relationships with other populations (parasitism and predatism).
Good examples of interspecific competition appear when rabbits, caves, rats compete for the same plant, or different fish and birds, such as the heron, vie for the same species of smaller fish. This is because these different species keep their populations in the same ecological niche. Competition is often so strong that some species eventually, as one example of an extrinsic homeostatic mechanism overriding an intrinsic homeostatic process is their disappearance or migration to other regions.
In this competition, the presence of adaptations among individuals in the population that promote better food search, speed, vision, and others can make the difference between elimination and survival.
Answer:
Kettlewell thought that if natural selection caused the change in the moth population, the following must be true: Heavily polluted forests will have mostly dark peppered moths. Clean forests will have mostly light peppered moths. Dark moths resting on light trees are more likely than light moths to be eaten by birds.
The salt solution is hypertonic to the plant cells. water from the plant cells seeped out. plasmolysis apply
"Eukaryote" roughly translates as "truly nucleated" and refers to organisms with a membrane-bound nucleus.
Such membrane-bound organelles are thought to have arisen via the invagination of the cell's own plasma membrane.
Other organelles such as the mitochondria and the chloroplast are believed to have once existed as separate organisms, but which were engulfed by other cells, forming a symbiotic relationship.