Quick check
bisphenol a (bpa) is a chemical used to make polycarbonate plastics. polycarbonate plastics are used in
certain food and drink packaging such as baby bottles, water bottles, and other drink containers. people
are exposed to bpa when they drink from these containers because the bpa migrates from the container
into the beverage. studies have shown that the ingested bpa may affect the brain, behavior, and
reproductive development in fetuses, infants, and children.
what is the scientific claim being made in this paragraph about bpa?
o bpa is a chemical used to make polycarbonate plastics.
o polycarbonate plastics are used to make baby bottles and water bottles.
bpa is not harmful to children or adults.
ingested bpa may affect the brain, behavior, and reproductive development in fetuses, infants, and
children.
done
intro
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ptid

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.