Commercial bananas are grown as a monoculture, with all banana plants cloned from one original banana plant. The commercial strains of bananas are seedless, so each new banana plant has to be manually planted from a cutting of an existing banana root. In the 1950s, the Gros Michel banana strain, the dominant export banana at that time, was destroyed by the fungus Fusarium oxysporum. A new Fusarium resistant variety, the Cavendish banana, was developed and is currently the banana strain grown for export. Recently, a Fusarium strain that successfully attacks the Cavendish strain has been documented. Which of the following best provides reasoning supporting a method that would help protect commercial banana crops from infection by pathogenic organisms such as Fusarium fungi? (A) The commercial banana strains should be exposed to X-rays to encourage random mutations that will then be passed to offspring, producing resistance to pathogenic organisms. (B) The Cavendish banana plants should be exposed to pathogenic organisms under controlled conditions, so the plants can be encouraged to mutate and develop resistance to the pathogens. (C) The commercial banana strains should not be grown in monocultures, since many pathogenic organisms are able to evolve rapidly in response to a single selective pressure. (D) Growing the Cavendish strain under different conditions will allow natural selection to produce the variation needed to resist infection by pathogenic organisms.

C. The commercial banana strains should not be grown in monocultures, since many pathogenic organisms are able to evolve rapidly in response to a single selective pressure.

Explanation:

Ideally, plants that undergo asexual reproduction are at risk of being wiped out by a single disease because they are all of the same susceptible variety.

The most practical solution for both economic and agricultural significance would be to remove the idea of monoculture. Planting other types of crops in the nearby area will provide some protection for the banana from certain pathogens.

For example in the event that there are F. oxysporum susceptible bananas another resistance specie or variety of banana is a practical addition to production. Additionally, other plants that are economically useful may also be introduced to the area to provide protection and slow the spreed of pathogens at the same time.

The answer is: (C) The commercial banana strains should not be grown in monocultures, since many pathogenic organisms are able to evolve rapidly in response to a single selective pressure.

Explanation:

A typical case of selection pressure is resistance to antibiotics, since selection pressure is defined as those factors that negatively affect organisms, since only organisms with an advantageous phenotype have the advantage of surviving, for example Antibiotics cause some selective pressure by eliminating bacteria that are susceptible to antibiotics, making those bacteria that are resistant survive. In this way, a monoculture would create a potential adaptation hazard for bacteria, since they could create patterns of resistance to specific selective pressures, which would make them grow rapidly.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.