The most unique feature of the echinoderms is their:a

digestive system.
b. nervous system.
c. closed circulatory system.
d. water vascular system.
e. mantle.


d

Biology & Microbiology

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________ microbiologists monitor community food establishments and water supplies in order to control the spread of communicable diseases.

Fill in the blank(s) with the appropriate word(s).

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Which of the following adds RNA nucleotides,

one at a time, during transcription?

a. RNA polymerase b. DNA polymerase c. RNA nuclease d. transfer RNA e. ribosomal RNA

Biology & Microbiology

AMP - activated protein kinase

a) undergoes allosteric regulation b) adds phosphate groups to serines and theonines in other enzymes c) is activated by both AMP and ADP d) all of the choices are correct

Biology & Microbiology

Levels of ecological organization

What will be an ideal response?

Biology & Microbiology