A doctor need to study chemistry: To know and understand the chemicals processes of matter in the body work which is for example insulin, DNA etc. and to study of all processes in a living organism. The three reasons to study chemistry is because chemistry can be useful in clearing up the natural world, preparing people for career opportunities and producing informed citizens. Some outcomes of modern research in chemistry can lead to technologies that aim to benefit the environment, preserve and produce energy, progress human life and multiply our knowledge of the universe. To help the citizen be a more informed citizen is to let them know how things work makes better decisions and use them better
The role a species plays in the ecosystem is called its niche.
Answer no 1 is correct :)
Arteries carry blood (with oxygen) from our heart out to your body, while veins carry blood (without oxygen) from your body to your heart. Arteries are strong, flexible blood vessels that are able to expand (get bigger) and contract (get smaller). They expand as your heart beats, and contract between heart beats. Veins are less flexible than arteries. They have valves (doors) that open and close to let blood through.
B i belive but u didnt post a pic or anything Hope this helps