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? sensors in the brain detect a lack of oxygen. the muscles in his body need more energy and therefore more oxygen. the body has too little carbon dioxide to maintain function. the body is using carbon dioxide instead of oxygen to make energy. blood pressure has decreased, so less blood is being pumped to the muscles.

well we can't tell you because we cant see the time give a screen shot or something.

it's the cell cycle, but cytokines is when the cell divides.

theres 3 stages interphase,mitosis,and cytokines.

interphase prepares the cell for division.

mitosis is the process of dividing the cell,it has 4 parts interphase,anaphase,metaphase,and telophase.

lastly there's cytokines,that's when the cell divides into 2 daughter cells

primary succession occurs in essentially lifeless areas regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier. secondary succession occurs