Predict what would happen if you used the pH indicator thymophthalein instead of phenol red in the above setup. Thymophthalein solution appears colorless below pH 9.3, but blue at higher pH.

What will be an ideal response?


Phenol red turns yellow when exposed to acid. There would be no color change unless the acidity of the solution increased above 9.3. If the pH increased above 9.3, the solution would turn blue. As the Elodea stems are placed into this solution, the color would have disappeared as the acid was “picked up”.

Biology & Microbiology

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At what checkpoint(s) does the cell arrest in response to DNA damage?  

A.  G1/S B.  G2/M C.  spindle D.  G1/S and G2/M E.  G2/M and spindle

Biology & Microbiology

The part of a neuron that conducts an electrical signal towards other neurons is/are the

a. dendrites. b. cell body. c. axon. d. dendrites and axon. e. dendrites, cell body and axon.

Biology & Microbiology

The breakdown of larger molecules into smaller ones

What will be an ideal response?

Biology & Microbiology

Which three stages or transitions in the cell cycle seem to serve as points of control (checkpoints)?

What will be an ideal response?

Biology & Microbiology