Living cells have an intact phospholipid bilayer that separates the cell from its external environment; this structure is commonly referred to as the

a. nucleus.
b. mitochondria.
c. endoplasmic reticulum.
d. plasma membrane.


Ans: d. plasma membrane.

Biology & Microbiology

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a. spectrograph. b. x-ray. c. stereograph. d. micrograph. e. microphoto.

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Why is only one strand of DNA transcribed into mRNA?

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The ATP synthase complex in the thylakoid membrane

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Biology & Microbiology