Where do cells get the resources
they need to aid in an organisms
survival?

On a backpacking trip, kenny hikes all day at a steady pace, covering 30 kilometers and burning 4000 calories. at the school track, janelle runs the 100-meter sprint in 13.5 seconds, burning 10 calories. afterward, janelle’s leg muscles are aching and she is breathing hard, while kenny maintains normal breathing all day, even though he burns 400 times more calories than janelle. which two statements offer the best explanation for this phenomenon? a. if the aerobic pathway—cellular respiration—cannot meet the energy demand, then the anaerobic pathway—lactic acid fermentation—starts up, resulting in lactic acid buildup and "oxygen debt." b. aerobic cellular respiration produces more energy, but its use is limited because of lactic acid buildup in the muscles and the resulting "oxygen debt." c. after about 90 seconds of intense exercise, the muscles become depleted of oxygen, and anaerobic respiration can no longer function to produce atp, resulting in "oxygen debt." d. the rate of energy demand determines how the muscles will obtain energy, either from cellular respiration or from lactic acid fermentation if not enough oxygen is present.

Select all the correct answers. for a claim about the natural world to be considered scientific, what attributes must it have? a).it must be applicable to future events and occurrences. b)it must be based on scientific observations that can be repeated in a controlled setting. c)it must be open to modification if new evidence doesn't completely support it. d)it must be consistent with only a small portion of relevant observations or data.

If it turned out dinosaurs were colorblind, how would this affect some assumptions scientists have made about them?