题目内容

Mineral deficiencies can often be detected by specific symptoms such as chlorosis(loss of chlorophyll resulting in yellow or white leaf tissue), necrosis(isolated dead patches), anthocyanin formation(development of deep red pigmentation of leaves or stem), stunted growth, and development of woody tissue in an herbaceous plant. Soils are most commonly deficient in nitrogen and phosphorus. Nitrogen-deficient plants exhibit many of the symptoms just described. Leaves develop chlorosis; stems are short and slender; and anthocyanin discoloration occurs on stems, petioles, and lower leaf surfaces. Phosphorus-deficient plants are often stunted, with leaves turning a characteristic dark green, often with the accumulation of anthocyanin. Typically, older leaves are affected first as the phosphorus is mobilized to young growing tissue. Iron deficiency is characterized by chlorosis between veins in young leaves.
The word "exhibit" in the passage is closest in meaning to

A. fight off
B. show
C. cause
D. spread

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Why does the professor mention the Kennedy Center and Lincoln Center?

A. To give examples of institutions that benefit from corporate support
B. To illustrate why some artists oppose the building of cultural centers
C. To show how two centers were named after presidents who supported the arts
D. To name two art centers built by the government during the Depression

According to the discussion, in what two ways was the Federal Art Project successful? Choose 2 answers.

A. It established standards for art schools.
B. It provided jobs for many artists.
C. It produced many excellent artists.
D. It gave many people greater access to the arts.

What important point does the professor make about the area where the rocks are found?

A. It has been the site of Earth"s highest wind speeds.
B. It is subject to laws that restrict experimentation.
C. It is accessible to heavy machinery.
D. It is not subject to significant changes in temperature.

According to the professor, what have the researchers agreed on?

A. The rocks cannot move after ice storms.
B. The rocks do not move at night.
C. The rocks never move in circles.
D. The rocks are not moved by people.

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