Inglés
Choose the correct answer for each question according to the information in the text. Each line is numbered to help you identify them quickly.
| Sunflowers Make Bees Poop—a Lot. Here's Why That's Good | |
|---|---|
| Paragraph | Text |
| [1] | Bumblebees and other pollinators face many threats, including pesticide exposure, |
| [2] | climate change, habitat loss due to agriculture and development, and pathogens |
| [3] | that ravage multiple species. But a recent finding may help lighten their load. |
| [4] | Previous studies have shown sunflower pollen can work like a medicine for |
| [5] | bumblebees afflicted by a parasite called Crithidia bombi, a single-celled organism |
| [6] | that takes up residence in the bee's gut [and harms their health]. But scientists couldn't |
| [7] | explain how sunflower pollen vanquished C. bombi—did it boost the bees' immune |
| [8] | function, or perhaps poison the parasite directly? |
| [9] | New research, published in the Journal of Insect Physiology, shows the answer is |
| [10] | deceptively simple. "Sunflower pollen makes bumblebees poo a whole lot," says lead |
| [11] | author Jonathan Giacomini, which flushes the parasite out. |
| [12] | Plant products like nectar and pollen are a treasure trove of potential insect medicines |
| [13] | that scientists are just beginning to understand, he adds. "There are natural things out |
| [14] | there that bees are interacting with that can be beneficial for them," Giacomini says. |
| [15] | And by making changes to the landscape, scientists hope we can help give bees a |
| [16] | fighting chance. |
| [17] | Plant power |
| [18] | If you happen upon a fuzzy, buzzing, flying creature in eastern North America, there's |
| [19] | a strong chance it's a common eastern bumblebee (Bombus impatiens). Yellow and |
| [20] | black striped with a rump covered in soft hairs, they're social insects that live in |
| [21] | colonies and love a good crevice—they build their homes in birdhouses, woodpiles, |
| [22] | abandoned burrows, and dense grasses. |
| [23] | [They] are important pollinators, both in the wild and in agriculture, where they're raised |
| [24] | and used to pollinate crops including tomatoes and pumpkins. Like other pollinators, |
| [25] | bumblebees face many threats, and C. bombi isn't even the biggest bumblebee |
| [26] | bugaboo. On its own, the parasite doesn't have much of an effect on a bumblebee's |
| [27] | health. But when food is scarce, C. bombi can shorten a bee's lifespan and even |
| [28] | reduce the number of young queens a colony can produce. |
| [29] | Lynn Adler is an evolutionary ecologist at the University of Massachusetts Amherst |
| [30] | who studies interactions between plants and insects. For years, she and longtime |
| [31] | collaborator Rebecca Irwin at North Carolina State University suspected pollinators |
| [32] | might be getting dosed by flowers since plants often invest chemically active |
| [33] | compounds into their nectar and pollen to help their genetic payload arrive at |
| [34] | its destination. |
| [35] | "Many plant defensive compounds can be medicinal at certain doses," Adler says. After |
| [36] | all, "most of our human medicines come from plants." |
| [37] | Giacomini discovered the effect of sunflower pollen as an undergraduate working in |
| [38] | Adler's lab in 2018. From [these] very first tests, sunflower pollen dramatically reduced |
| [39] | C. bombi parasite load in common eastern bumblebees, often clearing infection |
| [40] | completely. "We've been shocked at how consistent and effective sunflower pollen |
| [41] | has been," Adler says. |
| Elizabeth Anne Brown, National Geographic | |
Who supports the idea that many human medicines are made of natural sources?
Exani II -> Módulos Específicos -> Historia
UNAM -> BIOLOGÍA SIMULADOR PARA LA UNAM
UNAM -> BIOLOGÍA SIMULADOR PARA LA UNAM
UNAM -> QUIMICA SIMULADOR PARA LA UNAM
UNAM -> HISTORIA DE MÉXICO SIMULADOR PARA LA UNAM
Exani II, Exani II -> Comprensión Lectora
¿A qué concepto se refiere el autor en la parte del texto que aparece en negritas?
En el sentido social y político se concibe como la posibilidad de autonomía e independencia para regir el destino propio y el de una comunidad sin interferencia de otras; esto no significa evadir la ley sino actuar de acuerdo a ella.
Exani II, Exani II -> Comprensión Lectora
Lee el siguiente párrafo y contesta las preguntas.
No había nada que deseara hacer que no pudiese igualmente dejar de hacer. Incluso de niño, cuando no me faltaba nada, deseaba morir: quería rendirme porque luchar nada tenía sentido para mí. Consideraba que la continuación de una existencia que no había pedido no iba a probar, verificar, añadir ni sustraer nada. Todos los que me rodeaban eran unos fracasados o, sino, ridículos. Sobre todo, los que habían tenido éxito. Éstos me aburrían hasta hacerme llorar.
Era compasivo para con las faltas, pero no por compasión. Era una cualidad puramente negativa, una debilidad que brotaba ante el simple espectáculo de la miseria humana. Nunca ayudé a nadie con la esperanza de que sirviera de algo; ayudaba porque no podía dejar de hacerla. Me parecía inútil cambiar el estado de cosas; estaba convencido de que nada cambiaría sin un cambio de corazón, ¿y quién podía cambiar el corazón de los hombres? De vez en cuando un amigo se convertía; era algo que me hacía vomitar. Tenía tan poca necesidad de Dios como él de mí.
MILLER,
Henry Trópico de capricornio
¿Por qué el deseo de no hacer, la idea de fenecer y el no querer luchar del autor?
Exani