Research generally supports the theory that caffeine may enhance performance in long distance endurance events. which of the following is the least likely hypothesis?
(a) it may exert a psychologically stimulating effect.(b) it stimulates the release of epinephrine from the adrenal gland.(c) it decreases the use of both free fatty acids and muscle glycogen.(d) it may decrease the perception of effort during exercise.(e) it may exert a direct effect on the muscles to increase muscle contractile force.

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.

Which statement describes the punctuated equilibrium theory?

The table below shows the elements that mainly comprise each of the four layers of earth: elements in layers layer main elements crust oxygen, silicon mantle iron, magnesium outer core iron, nickel inner core iron which of these elements make up the layer that is 0.2 to 1.1 percent of earth's total diameter?