Internal support system
that allowed for large,
heavy bodies

Dr. bob hypothesizes that drug x causes cuts to heal more quickly. he performs a medical experiment on a group of 100 people and confirms his original hypothesis. in the control group, a 1 cm cut took seven days to heal. in the experimental group, a 1 cm cut took four days to heal. what should dr. bob do next? a) repeat the experiment for accuracy. b) begin selling drug x to the public. c) write a scientific theory about drug x. d) publish the results of the experiment in a scientific journal.

Which of the following represents the chemical reaction of hydrazine and hydrogen peroxide to produce nitrogen and water? a. nitrogen + hydrogen peroxide → hydrazine + water b. nitrogen + water → hydrazine + hydrogen peroxide c. hydrazine + hydrogen peroxide → nitrogen + water d. water + hydrogen peroxide → nitrogen + hydrazine

Match the following terms describing electrical events with the correct phases of the cardiac cycle. the ventricular muscle cells depolarize at the start of this phase. during this phase, na+ entry through the funny channels causes the pacemaker potential of sa nodal cells to gradually become less negative until it reaches threshold. the ventricular muscle cells repolarize right before this phase. the cytosolic concentration of calcium in the contractile cells of the ventricle is highest during this phase. a. isovolumetric relaxation b. ventricular ejection c. isovolumetric contraction d. ventricular filling