Kingdom: Arthropoda; Class Insecta 3 Main Body sections: head, thorax and abdomen 3 Legs 1 pair of antennae Wings are usually present (but many wingless)

Reproduction: Sexual Separate sexes Sperm must be deposited through copulation Exception: some species develop diploid “eggs” without sperm (parthenogenesis). In bees, fertilized eggs become females, unfertilized eggs become male. Mating is often accompanied by complicated courtship rituals…dancing, certain flight patterns, etc Most deposit eggs in a sheltered place, while some species retain the eggs until they hatch.

Growth & Development Metamorphosis: means “change” Incomplete metamorphosis means that the young forms are physically identical to the adult from except they are is smaller. Approx. 12% of all insects grow and develop in this manner. Complete metamorphosis means that each stage looks completely different t than the other. Nearly 88% of insects grow and develop in this manner.

Regulation Simple brain in the head section and central nervous system running through the thorax and abdomen SENSES Many insects such as grasshoppers, crickets and circadas can hear with structures called tympanum membranes. They may be located on either side of the head, or in the case of crickets on their front legs. Some insects cannot hear sounds at all. Insects have an amazing sense of touch usually received through sensory hairs. They detect not only the change in their body if touched, but they are able to determine changes in wind direction, air pressure. They also can detect changes in humidity, temperature, and in some case the earth’s magnetic field. Insects have a highly developed sense of smell. This is due to chemical receptors on their antennae. They can detect pheromones (chemical signals) to help find mates. They can also detect the chemicals from flowers and other food sources. http://www.cals.ncsu.edu/course/ent425/tutorial/senses.html Most adult insects have two compound eyes for sight . They are very different from our human eyes. Each compound eye consists of many single eyes, facets, which are independent from each other. Insects that live underground have small eyes or none at all www.geocities.com/.../ScientificInsect.htm

Transport: Open circulatory system: In an open system, blood (usually called hemolymph) spends much of its time flowing freely within body cavities where it makes direct contact with all internal tissues and organs. In closed systems, blood remains in vessels throughout the body. Open circulatory systems pump blood into a hemocoel with the “blood” diffusing back to the circulatory system between cells. Hemolymph is pumped by a heart into the body cavities, where tissues are surrounded by the fluid. The resulting flow is sluggish.

Excretion: Malpighian tubules  These long, spaghetti-like structures extend throughout most of the abdominal cavity where they serve as excretory organs, removing nitrogenous wastes (principally ammonium ions, NH4+) from the hemolymph.  

Respiration Air enters the insect's body through valve-like openings in the exoskeleton.   These openings (called spiracles) are located on the thorax and abdomen of most insects -- usually one pair of spiracles per body segment Air then enters a longitudinal tracheal trunk, eventually diffusing throughout a complex, branching network of tracheal tubes that subdivides into smaller and smaller diameters and reaches every part of the body. At the end of each tracheal branch, a special cell (the tracheole) provides a thin, moist interface for the exchange of gasses. Air sacs, balloon-like structures, may store a reserve of air. http://www.cals.ncsu.edu/course/ent425/tutorial/respire.html  

Synthesis Hydrolysis; dehydration reactions to form larger molecules Cellular respiration to form ATP.

Nutrition: Heterotrophic Insects require basically the same type of molecules that humans do in order to survive: carbohydrates, proteins, lipids and nucleic acids. Variety of food sources: nectar, sap, other insects, decaying organisms, etc Insects cannot digest carbohydrates such as cellulose found in plant cell walls? BUT, termites are insects!!!! They are able to digest cellulose because of symbiotic bacteria living their gut that produces digestive enzymes to break down the cellulose.