The west Nile Virus is pathogen which caused the West Nile fever and encephalitis. The pathogen was introduced in 1999 in the Western Hemisphere and infected a major population in new york. It then expanded to 12 states and district of columbia. The major carrier of the pathogen was Avian and Mosquitoes species. In between 1999 to 2008, nearly 2500000 people were infected and nearly 1500 people died. Also there were thousands of cases of encephalitis or meningitis.
Answer:Organ
Explanation:An organ may be defined as a group of tissues which perform similar functions. Organs can be found in both plants and animals,functionally related organs often cooperate to form systems. These organs are interdependent on each other to make up organ systems. Organ systems can be found in the different parts of the body. For instance,the esophagus,stomach and liver make up the digestive system and in the excretory system the skin and kidney are examples of the organs that can be found here. The main tissues of an organ tend to have the same embryological origin. This simply means that they arise from the same germ layer and by germ layer we mean the primary layer of cells that form during embryonic development. In plants however,the main organs are the roots,stem and leaves whose primary functions are to give nourishment to the plant. Reproductive organs of plants include the seed,flowers and spores which maintain the basic life processes of the plant.
<span>The contraction of the diaphragm causes an increase in the height of the thoracic cavity. Contraction of the intercostal muscles causes the diameter of the thoracic cavity to increase. The increased thoracic cavity volume brings a volume increase in intrapulmonary volume, which causes a drop in pressure relative to atmospheric pressure. Air rushes into lungs along this pressure gradient until intrapulmonary and atmospheric pressure are equal.</span>
The burning of fossil fuels can cause smog and acid rain.
The process by which forms of life having traits that betterenable them to adapt to specificenvironmental pressures, as predators, changes in climate, or competition for food or mates,will tend to survive andreproduce in greater numbersthan others of their kind, thusensuring the perpetuation of those favorable traits in succeeding generations.