更多"The author refers to lead and cadmi"的相关试题:
[单项选择]The author refers to "external mechanisms" primarily in order to
A. suggest that a biochemical analysis of dinosaur thermoregulation might be a waste of time
B. suggest that other means than warm-bloodedness may account for evidence of dinosaur thermoregulation
C. explain why scientists are interested in looking for an absence of seasonal variations in oxygen 18 traces
D. suggest that metabolic rates, not warm-bloodedness, may have been the key factor in certain dinosaurs’ survival
E. imply that other factors beside temperature may dictate the ratio of oxygen isotopes
[单项选择]The author refers to the example of Oedipus the King (line 15) most likely in order to
A. suggest that Aristotle did not consider Greek tragedy which involved accidental crimes to be truly sound in dramatic terms
B. argue that exceptions existed in Greek tragedy to Aristotle’s principle that intentional crimes were more impressive
C. suggest that protagonists who committed accidental crimes in Greek tragedies tended to be better received than intentional criminals
D. to suggest that the spectator of a tragedy featuring an accidental crime would himself feel pity and terror
E. illustrate an application of Aristotle’s theory of character to a specific dramatic example
[填空题]By "functionally illiterate", the author refers to ______.
[单项选择]The author refers to charms and quarks (lines 3-4) primarily in order to
A. demonstrate the similarity between these particles and the gluon
B. make a distinction between apposite and inapposite terminology
C. offer an objection to suggestions of similar frivolous names
D. provide illustrations of idiosyncratic nomenclature in contemporary physics
E. cite preliminary experimental evidence sup-porting the existence of gluons
[单项选择]The word "it" in line 22 refers to
(a) a nutrient solution
(b) a glass flask
(c) boiling
(d) spontaneous generation
[填空题]The word "we" in Line 3, Para 5 refers to "British people".
[单项选择]The author mention "l.0mm" in line 14 in describing the
(a) thickness of a layer of organisms that was deposited on an object
(b) diameter of the fibers that were in the guncotton filters
(c) thickness of the microscope slides that were used
(d) size of the particles that that were collected
[单项选择]Phatic communication refers to
A. language’s function of the expression of identity.
B. social interaction of language.
C. language’s function of expressing itself.
D. sociological use of language.
[填空题]What information does the lead provide
A lead answers certain questions that might be asked by ______.
[单项选择]Distinctive sound refers to（）
A. allomorph
B. phoneme
C. phone
D. minimal pairs
[填空题]What kind of life she would lead
She would lead ______ life.
[单项选择]
Lead Poisoning: A Silent Epidemic
How much lead is harmful Until the 1970s, exposure to lead was considered dangerous only at blood levels associated with extreme symptoms of poisoning: convulsions (惊厥), brains swelling, acute kidney disease, stomach pains and hallucinations (幻觉). But low -level lead poisoning can cause symptoms that, while subtle, are no less serious. As a result, the CDC has continually lowered the point at which patients should be treated for lead poisoning.
One of the most influential study of lead’ s low - level effects was published by Herbert Needleman, professor of psychiatry at the University of Pittsburgh Medical School. Testing first and second grade students in the Boston area, he found the lowest I. Q. , academic achievement, language skills and attention span among children with the highest tooth levels (起损害作用的量) of lead. "None of their lead levels exceed the CDC’s 1979 toxicity threshold. "Says Paul Mu
A. the amount of exposure was large.
B. it caused extreme symptoms of poisoning.
C. it caused symptoms whether serious or not.
D. poisoning had led to death among the poisone
