Landfills are harfull to the environment because many substances cannot decompose like styrofoam and all this matter keeps building up but never decomposes
"(1) Human population growth reached 6.8 billion in 2010 and it continues to increase" is what led to the other <span>three, since all of these happen from human activity. </span>
Answer:
Circulatory would be the answer.
Explanation:
The defense system of the human body is made up of entire organs and vessel systems like the lymph vessels, but also of individual cells and proteins. The inner and outer surfaces of the body are the first barriers against pathogens (germs). These surfaces include the skin and all mucous membranes, which form a kind of mechanical protective wall.
Several things support this protective wall:
<span><span>- The body’s own antibacterial substances can disable different pathogens from the environment at an early stage. A certain enzyme found in saliva, the airways and tear fluid destroys the cell walls of bacteria.
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- Many pathogens that are breathed in get stuck to mucus in the bronchi and are then moved out of the airways by hair-like structures called cilia.
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- Most pathogens that enter the body together with food are usually stopped by stomach acid.
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- Normal flora, harmless bacteria that reside on the skin and many mucous membranes in the body, also help to protect the body.</span></span>
The cough and sneeze reflex can also help to remove pathogens.
Hope this helps (:
THE VESSEL IS THE MIDDLE HEPATIC VEIN.
The hepatic veins are the one that carry oxygen depleted blood from the liver into the inferior vena cava. They also transport blood that has been drained from the colon, pancreas, stomach and the small intestines. The hepatic veins are three in number, they are: right hepatic vein, middle hepatic vein and the left hepatic vein.
