During mitosis, chromosomes are moved and separated through the use of spindles composed of structures. a) endoplasmode b) integument c) macrofilament d) microtubule

Explain how scientists use geologic time to determine the age of landforms.

All ova contain sex chromosomes corresponding to: x y xx xy

Which of the following statements best distinguishes a hypothesis from a theory? a. theories are hypotheses that have been proved. b.hypotheses are guesses; theories are correct answers c. hypotheses usually are relatively narrow in scope; theories have broad explanatory power. d. theories are proved to be true; hypotheses are often contradicted by experimental results.