According to the Bohr model, the wavelength of the light emitted by a hydrogen atom when the electron falls from a high energy (n = 4) orbit into a lower energy (n = 2) orbit.
A network of arteries and veins also carry blood throughout the body: Arteries transport blood from the heart to the body tissues. Veins carry blood back to the heart.ow the heart works. The heart is a large, muscular organ that pumps blood filled with oxygen and nutrients through the blood vessels to the body tissues. It's made up of: Four chambers. The two upper chambers, the atria, receive and collect blood.
The tiniest blood vessels, called capillaries, take blood. directly to and from the cells. The network of blood vessels. allows oxygen and nutrients to be delivered to all cells of the. brain continuously. Each artery supplies blood to specific areas of the brain. Some. areas of the brain are supplied by more than one artery.