Question

Jon likes hiking. He observes that whenever he hikes up a hill, he breathes heavier than when he is on flat ground. Which two statements explain why this happens?
A. Sensors in the brain detect a lack of oxygen.
B. The muscles in his body need more energy and therefore more oxygen.
C. The body has too little carbon dioxide to maintain function.
D. The body is using carbon dioxide instead of oxygen to make energy.
E. Blood pressure has decreased, so less blood is being pumped to the muscles.

Answer 1

this is because of the following sentences :- .

a) sensors in the brain detect the lack of o2 and,

b) the muscle in his body need more energy and more oxygen ,

now , let us see why this is so :-

a) sensor in the brain detect the lack of o2 because when ever we go on very high level from the surface of earth like on mountain , or any hilly area there is a lack of o2 in air . there is a lack of o2 in air at high level so that's why happening first .

b) when ever a person do some suddenly exercise or some activities this causes the production of lactic acid in our muscles and need more o2 to fulfil at that time . so that's why this happening with him in second situation.

hope it helps