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how to write a seminar on the topic cockroach

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UXL Encyclopedia of Science

UXL Encyclopedia of Science

The Columbia Encyclopedia, 6th ed.

World Encyclopedia

The Oxford Pocket Dictionary of Current English

A Dictionary of Zoology

The Concise Oxford Dictionary of English Etymology

A Dictionary of Biology

Oxford Dictionary of Rhymes

The Gale Encyclopedia of Science

The Gale Encyclopedia of Science

Cockroaches

UXL Encyclopedia of Science 
COPYRIGHT 2002 The Gale Group, Inc.

Cockroaches

Cockroaches are winged insects found in nearly every part of the world. Although they are one of the most primitive living insects, they are very adaptable and highly successful. Some of the species have invaded human habitats and are considered pests since they can spread disease.

"Crazy bug"

Cockroaches or roaches belong to the order Blattaria, which means "to shun the light." They were given this scientific name because they sleep and rest during daylight hours and come out mainly at night. Their common name, however, is a version of the Spanish word cucaracha, which means "crazy bug." If you have ever seen one running away from you in a typical wild and zigzagging way, you know how they got their name.

There are some 4,000 species or kinds of cockroaches living in nearly every habitat except Antarctica. All of them prefer to live where it is warm and moist, or where they can at least get water, so it is not surprising that they will move into people's homes if given the chance. Actually, only about 35 of these species are ever associated with people, and the other nearly 4,000 species live throughout the world, although the largest numbers are found in the tropics.

Cockroaches can be interesting, and some would even say fascinating. They can range in length from only 0.1 to 3.2 inches (2.5 to 8.1 centimeters). They seldom use their wings to fly, although some can fly around. Their bodies have a waxy covering that keeps them from drowning. They also can swim and stay underwater for as long as ten minutes. They will rest in one spot without moving for eighteen hours a day, and can go a long time without food.

They eat only at night. As for what they eat, they are omnivorous (pronounced om-NIH-vaw-rus), meaning that they can and will eat anything, plant or animal. The more we learn about their diet, the more disgusting they seem, since they eat everything, including animal feces. Although they will eat wood, which is made up of cellulose, they are unable to digest it on their own and, thus, depend on certain protozoa (pronounced pro-toe-ZO-uh) or single-celled organisms that live in their digestive tracts or gut, to break the cellulose down. They make sure they always have these protozoa in their systems by eating the feces of other cockroaches.

Words to Know

Exoskeleton: An external skeleton.

Omnivorous: Plant- and meat-eating.

Oviparous: Producing eggs that hatch outside the body.

A versatile insect

Cockroaches are escape artists whose zigzag darting is done at what seems lightning speed. They can climb easily up vertical surfaces and have such flat bodies that they can hide in the tiniest of cracks and crevices.

They have compound eyes (honeycomb-like light sensors) and antennae that are longer than their bodies, which they use to taste, smell, and feel. They even have a special organ in their mouths that allows them to taste something without actually eating it. Each of their six strong legs has three sets of "knees," all of which can sense vibrations and therefore serve as an early warning system. They also have little motion detectors on their rear end, which explains why they are so hard to catch and stomp. Although females mate only once in their lifetimes, they will stay fertilized all their lives and keep producing eggs without the help of a male cockroach.