About ____ species of birds have been described

a. 1,000
b. 2,000
c. 4,500
d. 9,000
e. 20,000


d

Biology & Microbiology

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The class of proteobacteria that may be incorporated into the gamma proteobacteria is the ________.

A. delta proteobacteria B. alpha proteobacteria C. beta proteobacteria D. epsilon proteobacteria

Biology & Microbiology

Which solution will cause water to be drawn out of a cell?

a. Hypotonic b. Isotonic c. Hypertonic d. Catatonic

Biology & Microbiology

Cells that de-differentiate, lose cell cycle control, and lose their attachment to the surrounding cells, are known as ________.

What will be an ideal response?

Biology & Microbiology

An isotope contains more or fewer electrons than normally found in an atom of a particular element and may give off radiation.

a. true b. false

Biology & Microbiology