Conducting tubes of phloem consist of stacks of ____.

A. dead sieve elements
B. living sieve elements
C. dead vessel elements
D. living vessel elements
E. dead companion cells


Answer: B

Biology & Microbiology

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Which of the following statements is true regarding T cell receptors? Select all correct

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________ reactions require an input of energy when electrons are gained, such as in the conversion CO2 ? CH4

Fill in the blank with correct word.

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Alexander Fleming kept finding mold contamination that was killing his bacterial cultures. This observation eventually lead to the development of the antibiotic penicillin. Why would a fungus produce a compound that is selectively toxic to bacteria?

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Biology & Microbiology