Friday, May 28, 2010

Mosquito Bite







How Does a Mosquito Bite?








Introduction


Mosquitoes are one of the most resilient and annoying creatures on earth. They are also one of the largest spreaders of diseases in the world. The mosquito thrives in any area that supplies stagnant water to reproduce in. The mosquito is mostly known for its bite. With the ability to bite even though clothing, the mosquito is a miraculous design in nature.


Anatomy


The mosquito's biting mechanism is made up of one part for the male, and two parts for the female. Both the male and female have a palpus. The palpus is just the mouth of the mosquito. The female has an additional structure called the proboscis. The male does not have this feature, which is why only female mosquitoes bite. The proboscis is actually a sheath that protects the inner tube that the mosquito uses to suck the blood from its prey. The outer sheath protracts when the mosquito wants to bite, and uses the tube inside to puncture the skin like a hypodermic needle.


Senses


Mosquitoes are attracted to specific stimuli that make certain people and animals more prone to bites than others. Mosquitoes have chemical sensors, heat sensors, and visual sensors. The chemical sensors allow the mosquito to detect lactic acid and CO2. These both are naturally produced by mammals as we breathe. The mosquitoes also use their heat sensors to find living things. The warmer the prey, the more likely they will be attracted to it. They also use visual sensors to watch for movement, as all living things move.


Why Bites Itch


When a mosquito bites they inject an anti-coagulant that keeps the blood from clotting as it is siphoned from your body. This also keeps the blood from clotting in the mosquito's stomach. These chemicals cause allergic reactions in most humans. The allergic reaction can vary from a small lump, to bites swelling across entire parts of the body.


Diseases


As the mosquito draws blood from its prey, there is the possibility that the blood from the last victim can be injected as the new blood is being drawn. Throughout history this has allowed diseases such as malaria, West Nile virus and yellow fever, to be easily spread in epidemic proportions in the United States as well as through the rest of the world.

Tags: blood from, blood from clotting, blood from prey, chemical sensors, from clotting