问题 选择题

黄豆芽和绿豆芽的食用部分主要是由种子的哪部分发育来的(  )

A.子叶

B.胚轴

C.胚根

D.胚芽

答案

黄豆和绿豆是双子叶植物种子,萌发的过程是:胚根首先发育成根.随着幼根的生长,胚轴逐渐在伸长,将两片子叶带出地面,子叶展开,露出胚芽.胚芽发育形成茎和叶.黄豆芽和绿豆芽的食用部位是连接胚根和胚芽的白色部分是胚轴.

故选:B

单项选择题

The “issues” reported were unthinkable. The physician who enrolled the most patients in the study, an Alabama weight-loss doctor, allegedly forged scores of signatures, enrolling “volunteers” every few minutes.

By the time of the FDA review, she was under criminal investigation. (She’s now in federal prison. ) Another key researcher had been put on probation by the California medical board for gross negligence. He was arrested shortly after the study ended, when police, called to his home on a domestic violence complaint, found him with a bag of cocaine and waving a loaded gun at imaginary people. The study was so riddled with fraud and error that FDA reviewers decided it was useless.

Yet Dr. Ross says he was told to reveal nothing about those problems to the advisory board, which recommended that the drug be approved. Later, he says, he was pressured to soften his report about Ketek’s liver toxicity to gain approval of higher-ups. Six million Americans have now used the drug, including hundreds of infants in a clinical trial designed to test Ketek’s effectiveness against ear infections. "How does one justify balancing the risk of fatal liver failure against one day less of ear pain" one FDA scientist, Rosemary Johann-Liang, protested—to no avail—in a memo to her superiors. Most ear infections clear up in a few days on their own, she says.

The agency says the controversy is overblown. "There was enough good, solid scientific data to make that decision. " Says FDA spokeswoman Julie Zawisza, pointing to what appeared to be a history of safe use of Ketek in other countries. Ketek has now been linked to 18 deaths and at least 134 cases of liver damage, according to an independent analysis using FDA data. The real toll, some researchers say, may be far greater.

Last October the FDA sent a warning letter to Sanofi-Aventis, Ketek’s maker, accusing the company of knowingly presenting compromised data to the agency, a charge the company denies. "We were not aware of the fraud," says spokeswoman Melissa Feltmann. "It was not until the FDA’s criminal investigators uncovered it that we became aware of it. "

The question remains, what did the FDA and the drugmaker know about the fake safety data, and when

Congressmen John Dingell and Bart Stupak, both Michigan Democrats, are investigating that mystery right now in Congressional hearings.

"Unfortunately. " Stupak says, "the truth comes too late for some victims. \

It can be inferred that Ketek is a medicine which ().

A. helps lose weight

B. helps improve memory

C. treats ear problems

D. treats liver problems

名词解释