A good reason for why tobacco smoke is considered a carcinogen is because it causes mutations leading to cancer.
D. fingernails
Skin, hair, and vertebrae are all the outer layer of the body and protect the body. The fingernails aren't part of that.
Answer:
Veins.
Explanation:
Heart is the main organs of circulatory system that transport blood in the body.Human heart is four chambered and separates the oxygenated and deoxygenated blood in the body.
Arteries are responsible for the passage of blood from heart to the body parts. The deoxygenated blood from the body collect in the veins and transfer to heart. Arteries has high pressure than veins and veins are thinner than artery.
Thus, the answer is veins.
Explanation:
I'm not sure but look online for the answers
Well one way is how hurricane winds and such can blow birds off course. Another is how when trees fall down that forces animals to relocate.
