Describe the route blood takes as it flows through the body, starting with the heart receiving oxygen-poor blood from the body.

the blood enters into the right atrium by inferior and superior vena cava--- left ventricle---pulmonary artery lungsleft atriumleft ventricle---aortadifferent body tissues.

Explanation:

The circulation in man is called the double circulation. Because in the heart the two types of blood circulate separately i.e. oxygenated blood/oxygen-poor blood and deoxygenated blood/oxygen-rich blood and they never mix.

The route of deoxygenated blood:

In the heart, the deoxygenated blood enters by the superior and inferior vena cava. Then this oxygen-poor blood stores in the right atrium and from there it passes into the left ventricle. The flow of blood from the right atrium to left ventricle occurs by the tricuspid valve.  

When the blood enters into the right ventricle the valves closed to stop the backflow of the blood.  

The blood from the right ventricle goes to the pulmonary artery by the pulmonary valve. From the pulmonary valve, the deoxygenated blood passes to the lungs. In the lungs, the deoxygenated blood/oxygen-poor blood gets purified.

The rout of oxygenated blood:

Now the blood becomes rich in oxygen and called oxygenated blood. This oxygenated blood enters into the left atrium by pulmonary vein. From the left atrium, the oxygen-rich blood moves into the left ventricle. Then the oxygenated blood reaches to the different parts of the body by the aorta.

In this way, the right half of the heart circulates the deoxygenated blood and the left half of the heart provides deoxygenated blood.

because the light is a great source of energy for the plants to survive. (i hope this )