Answer:
The left side of the heart receives oxygenated blood from the pulmonary vein and pumps it into the aorta, while the right side of the heart receives deoxygenated blood from the vena cava and pumps it into the pulmonary vein. The pulmonary vein and aorta also have valves connecting them to their respective ventricle.
Explanation:
Louder, because the sound would have a stronger pitch for the ear it is closer to
The circulatory system - hemoglobin in the blood transports oxygen :)
The correct answer is A.
Toxins and various pollutants increase in concentration through the food chain in a process called biomagnification. This means that the organisms on the top of the food chain, like the herring gull, have many times greater concentration of toxins than the lower food chain level organisms because they prey on lower food chain level organisms. If a herring gull ears 100 herrings, it will have a 100x times greater concentration of toxins in its body than a herring.
Answer:
1. The school board wants to clear the forest surrounding the local high school to build more fields for high school sports. Following environmental factors need to be investigated before clearing the land:
1. Destruction of natural ecosystem: As forest will be cut the land will be barren. There will be loss , extinction and migration of faunal species. So, the normal balance of ecosystem will b disturbed.
2. Chances of climatic fluctuations: As, forest will be cleared, the water, carbon and oxygen cycle in the atmosphere will be disturbed. The region may not acquire adequate rainfall, temperature of the area will change drastically.
3. Soil erosion: As, forest will be cleared the soil will not be hold up and the loose soil gets wiped out from the location by water or air.The cutting of trees can cause flooding from nearby water body.
2. Two ways to reduce air pollution and slow climatic change are:
1. Control use of fossil fuels: Fossil fuels like coal, petrol, kerosene are used in automobiles, industries and house hold activities. These fossil fuels are organic in nature and adds up carbon dioxide, carbon monoxide, nitrogen dioxide gases in air and raises the atmospheric temperature and are responsible for air pollution. Therefore, the use of fossil fuel should be in control manner.
2. Planting more number of trees: The trees are responsible for fixing atmospheric carbon from air for photosynthesis. So, they can decrease the amount of atmospheric carbon abundantly present in forms of carbon dioxide and carbon monoxide, which are chief air pollutants. These carbon products are responsible for raising temperature so planting of trees can prevent raise of temperature.
