Answer:Of the more than 7,000 chemicals in tobacco smoke, at least 250 are known to be harmful, including hydrogen cyanide, carbon monoxide, and ammonia (1, 2, 5). Among the 250 known harmful chemicals in tobacco smoke, at least 69 can cause cancer. Explanation:
It help warm and moisten incoming air
Answer:
D.) Oxygen-poor
Explanation:
The pulmonary veins are the vessels that carry the oxygen-rich blood to the left atrium
Answer:
Human subject research is systematic, scientific investigation that can be either interventional (a "trial") or observational (no "test and Human subject research can be either medical (clinical) research or non-medical (e.g., social science) research.