(PUCCAMP) Certas plantas só florescem em determinados meses do ano e o fator preponderante que exerce o papel de relógio biológico para elas é

(FUVEST 2016 1° FASE) Chumaços de algodão embebidos em uma solução de vermelho de cresol, de cor rosa, foram colocados em três recipientes de vidro, I, II e III, idênticos e transparentes. Em I e II, havia plantas e, em III, rãs. Os recipientes foram vedados e iluminados durante um mesmo intervalo de tempo com luz de mesma intensidade, sendo que I e III foram iluminados com luz de frequência igual a 7,0 x 10¹⁴ Hz, e II, com luz de frequência igual a 5,0 x 10¹⁴ Hz. O gráfico mostra a taxa de fotossíntese das clorofilas a e b em função do comprimento de onda da radiação eletromagnética. Considere que, para essas plantas, o ponto de compensação fótica corresponde a 20% do percentual de absorção.

Note e adote:

•  As plantas e as rãs permaneceram vivas durante o experimento.
•  As cores da solução de cresol em ambientes com dióxido de carbono com concentração menor, igual e maior que a da atmosfera são, respectivamente, roxa, rosa e amarela.
•  Velocidade da luz = 3x10⁸ m/s
•  1 nm = 10^--9 m

É correto afirmar que, após o período de iluminação, as cores dos chumaços de algodão embebidos em solução de cresol dos recipientes I, II e III ficaram, respectivamente,

  Uma elipse é uma seção plana de um cilindro circular reto, em que o plano que intersecta o cilindro é oblíquo ao eixo do cilindro (Figura 1). É possível construir um sólido de nome elipsóide que, quando seccionado por três planos perpendiculares entre si, mostram elipses de diferentes semieixos a, b e c, como na Figura 2. O volume de um elipsóide de semieixos a, b e c é dado por 

Considere que um agricultor produz melancias, cujo formato é aproximadamente um elipsóide, e ele deseja embalar e exportar suas melancias em caixas na forma de um paralelepípedo retângulo. Para melhor acondicioná-las, o agricultor preencherá o espaço vazio da caixa com material amortecedor de impactos (palha de arroz/serragem/bolinhas de isopor).

Suponha que sejam a, b e c, em cm, as medidas dos semieixos do elipsóide que modela as melancias, e que sejam 2a, 2b e 2c, respectivamente, as medidas das arestas da caixa. Nessas condições, qual é o volume de material amortecedor necessário em cada caixa?

(UNIFESP) The Rise of Antibiotic Resistance

By The Editorial Board

May 10, 2014

The World Health Organization has surveyed the growth of antibiotic-resistant germs around the world – the first such survey it has ever conducted – and come up with disturbing findings. In a report issued late last month, the organization found that antimicrobial resistance in bacteria (the main focus of the report), fungi, viruses and parasites is an increasingly serious threat in every part of the world. “A problem so serious that it threatens the achievements of modern medicine,” the organization said. “A post-antibiotic era, in which common infections and minor injuries can kill, far from being an apocalyptic fantasy, is instead a very real possibility for the 21st century.”

The growth of antibiotic-resistant pathogens means that in ever more cases, standard treatments no longer work, infections are harder or impossible to control, the risk of spreading infections to others is increased, and illnesses and hospital stays are prolonged. All of these drive up the costs of illnesses and the risk of death. The survey sought to determine the scope of the problem by asking countries to submit their most recent surveillance data (114 did so). Unfortunately, the data was glaringly incomplete because few countries track and monitor antibiotic resistance comprehensively, and there is no standard methodology for doing so.

Still, it is clear that major resistance problems have already developed, both for antibiotics that are used routinely and for those deemed “last resort” treatments to cure people when all else has failed. Carbapenem antibiotics, a class of drugs used as a last resort to treat life-threatening infections caused by a common intestinal bacterium, have failed to work in more than half the people treated in some countries. The bacterium is a major cause of hospital-acquired infections such as pneumonia, bloodstream infections, and infections in newborns and intensive-care patients. Similarly, the failure of a last-resort treatment for gonorrhoea has been confirmed in 10 countries, including many with advanced health care systems, such as Australia, Canada, France, Sweden and Britain. And resistance to a class of antibiotics that is routinely used to treat urinary tract infections caused by E. coli is widespread; in some countries the drugs are now ineffective in more than half of the patients treated. This sobering report is intended to kick-start a global campaign to develop tools and standards to track drug resistance, measure its health and economic impact, and design solutions.

The most urgent need is to minimize the overuse of antibiotics in medicine and agriculture, which accelerates the development of resistant strains. In the United States, the Food and Drug Administration (FDA) has issued voluntary guidelines calling on drug companies, animal producers and veterinarians to stop indiscriminately using antibiotics that are important for treating humans on livestock; the drug companies have said they will comply. But the agency, shortsightedly, ¹has appealed a court order requiring it to ban the use of penicillin and two forms of tetracycline by animal producers to promote growth unless they provide proof that it will not promote drug-resistant microbes.

The pharmaceutical industry needs to be encouraged to develop new antibiotics to supplement those that are losing their effectiveness. The Royal Pharmaceutical Society, which represents pharmacists in Britain, called this month for stronger financial incentives. It said that no new class of antibiotics has been discovered since 1987, largely because the financial returns for finding new classes of antibiotics are too low. Unlike lucrative drugs to treat chronic diseases like cancer and cardiovascular ailments, antibiotics are typically taken for a short period of time, and any new drug is apt to be used sparingly and held in reserve to treat patients resistant to existing drugs. Antibiotics have transformed medicine and saved countless lives over the past seven decades. Now, rampant overuse and the lack of new drugs in the pipeline threaten to undermine their effectiveness.

(www.nytimes.com. Adaptado.) 

No trecho do quarto parágrafo (ref. 1), “has appealed a court order requiring it to ban the use of penicillin”, o termo em destaque se refere a:

A fosfatidilserina é um fosfolipídio aniônico cuja interação com cálcio livre regula processos de transdução celular e vem sendo estudada no desenvolvimento de biossensores nanométricos. A figura representa a estrutura da fosfatidilserina:

Com base nas informações do texto, a natureza da interação da fosfatidilserina com o cálcio livre é do tipo

Dado: número atômico do elemento cálcio: 20