<span>The complete statement is this: 'An increase in food and a decrease in predators would most likely increase genetic variation in a population. An increase in available food is an environmental factor which brings about genetic variation in the population of a specie.</span><span />
I remember answering this question. The answer would be Option B. Chitin, in arthropods, is a structural carbohydrate that forms their exoskeleton. It is a long chain of polymer of an N-acetylglucosamine. Hope this answers the question.\
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Please mark brainliest
Answer:
Oppositely charged particles attract each other, while like particles repel one another. Electrons are kept in the orbit around the nucleus by the electromagnetic force, because the nucleus in the center of the atom is positively charged and attracts the negatively charged electrons.
Explanation:
The hydrosphere makes up all of earths water, and has a secondary sphere called the cryosphere which encompasses all of Earth’s ice. This is important for all living things. Aquatic life lives in water, and land animals drink it to survive.
Answer:
a. The original spraying has caused a permanent mutation, giving the insects genetic resistance to the spray.
Explanation:
This is a practical evidences of mutation and variation, as mechanisms of evolution.
The insecticide is the selective pressure. As a results of continuous spray, the parents of the present mosquitoes must have acquired certain characteristics or traits by gene mutation which makes them resistant to the selective pressure (insecticides), and therefore survive the spray in the past.
Therefore when these resistant parents mated, with high reproductive success (leading to large gene pool of these traits,); variation in the genetic composition increases as the resistant gene is passed from generations to generations in the population. Therefore, the population of present day mosquito with genetic resistance to insecticides increases.They are therefore naturally selected, and able to survive as the present day mosquitoes with high resistance to insecticides.
