Which of the following describes a solution that contains a buffer? a. acetic acid is added to the solution, and the ph of the solution becomes lower. b. distilled water is added to the solution, and the ph of the solution does not change. c. formic acid is added to the solution, and the ph of the solution becomes higher. d. sodium hydroxide, a base, is added to the solution, but the ph of the solution does not change.

Which of these is true of the cytoplasm of an unfertilized egg? a. it is an unevenly distributed mixture of mrna, proteins, organelles, and other substances. b. it does not contain substances that are important in directing development. c. these substances are supplied by the sperm. d. it does not contain substances that are important in directing development. e. development is directed solely by the surrounding cells. f. it is a homogeneous mixture of mrna, proteins, organelles, and other substances. g. it does not contain substances that are important in directing development. h. these substances are produced by the dna of the fertilized zygote.