Lamarck was one of the first scientists to propose that species evolve by natural selection.

Growth of chest hair, deepening of the voice, and muscle growth are secondary sex characteristics. which most likely affects the development of these traits? testes ovaries prostate gland vulva

When analyzing tree rings, what do scientists assume a thin ring indicates?

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.