Microscopic organisms live at such extremes that, taking them into consideration, the thickness<span> of the </span>biosphere<span> is much greater. Culturable microbes have been found in the Earth's upper atmosphere as high as 41 km (25 mi).</span>
Recombination is the method by which organisms can randomly assort their genotypes amongst each other to create offspring with a different haplotype than either of its parents. This can be done by either copying sequences from one homologous chromosome to another (no physical exchange) or crossing over (physical exchange.
Crossing over is a mechanism in eukaryotes by which recombination can occur, in which the two homologous chromosomes contributed by both parents literally cross over and break at certain points to exchange certain sections of the chromosomes amongst each together.
Self fertilizing organisms typically do not produce offspring that are genetically identical. However, this has an inbreeding effect on its offspring, since it is recombining from the same genotype and so has a higher chance of producing homozygous offspring. This is very detrimental for mammals and some eukaryotes, but in some other organisms such as bacteria, homozygosity is typically not an issue.
<span>The role of a restriction enzyme is essentially used to cut a single gene from a larger piece of DNA. It has a very important role to play in experiments investigating cloning, and in the construction of particular DNA molecules.</span>
Answer:
Dr. Stott's belief about that the 9-year-olds will advance in knowledge based on instructions is based on the theory of cognitive development, proposed by Lev Vygotsky.
Explanation:
Theory of cognitive development -also called the socio-cultural theory of cognition- was put forward by the Russian-Jewish psychologist Lev Vygotsky, in which he expresses the influence of the socio-cultural environment on the learning process.
<u>For Vygotsky, children possess innate basic skills, such as attention, sensation, memory and perception, which develop over time</u>.
The process of cognitive development implies that the development of each child's basic skills requires the guidance of an adult, since -although there are skills that he does not understand or has not developed- he can learn them with the appropriate guidance and instructions.
Answer:
(C) The main predator of these fish is another species of fish on which alligators also prey.
Explanation:
The ecosystems are complex systems, and removing one species of them, always has a chain reaction and affects the population of the other species, be it in a positive or negative manner. In this case, the alligators prey upon fish, multiple different species. The alligators though have been removed from the ecosystem, thus the apex predator exists no more. This has opened up the top predator niche in the food chain in this particular ecosystem. The predatory fish species had no predators of its own, so its population increased, thus it needed more food, and that food was obtained by hunting the other fish species, resulting in a decline in the population of the other species of fish. Only when the carrying capacity is reached in the ecosystem for the predatory fish, the population of the other fish will stop declining.
