Answer:
The cardio-respiratory system works together to get oxygen to the working muscles and remove carbon dioxide from the body. During exercise the muscles need more oxygen in order to contract and they produce more carbon dioxide as a waste product.
Explanation:
D. A plant using sunlight to make good
Answer:
The lie is the second- only humans have DNA, all living things have DNA, so two would be your answer!
Answer:
heart rate to decrease
Explanation:
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B. Hereditary factors blend together to produce the traits of offspring