Which statement best describes how a catalyst can speed up a chemical reaction ? a. the catalyst makes lower energy pathways available. b. the catalyst increases the concentration of products. c. the catalyst binds to enzymes to release substrates. d. the catalyst increases the concentration of reactants.

Select the correct answer from each drop-down menu. in an experiment, dr. travis examined the effects of calcium intake on osteoporosis, a condition that causes an increased risk of bone fractures. the amount of calcium is variable. the risk of bone fractures .

50 points! which of the following is an inference? a burning candle is extinguished when it is covered with a jar. the candle burns longer than expected in a jar that has a plant in it. a plant lives longer than expected in a jar that has a burning candle. there is more oxygen in the jar because there is a plant in it.

The polio virus can cause skeletal muscle paralysis by destroying neuron cell bodies. what area of the spinal cord is destroyed