PSS 2401- Entomology Exam 1

Arthropods

- jointed appendages

Interesting facts

-2% of extant insects are responsible for destructive effect -remaining 98% (nearly 1 million species) are classified as either neutral or beneficial to humans

Characteristics of Insects

-Bilateral Symmetry -Exoskeleton -Jointed legs -Eyes -Antennae -Wings -Spiracle -Trachea -Hemolymph- no blood vessels -Brains- ganglia and paired ventral nerved cord

Father of the Classification System

-Carl Linnaeus -system of BINOMIAL NOMENCLATURE -authorities of names are those who named and described the species

Classification levels

-Kingdom (Animalia) -Phylum (Arthropoda) -Class (Insecta) -Order (Diptera, true flies) -Families (Muscidae) -Genus (Musca) -Species (domestica)

Bilateral Symmetry of Insects

-a basic body plan in which the left and right sides of the organism can be divided into approximate mirror images of each other along the midline

Antennae

-a pair on head -jointed -sensory (smell) -called "feelers"

Entomologist

-a person who studies insects

Invertebrates

-animals that do not have a backbone

Sequencing of genes

-are producing a revolution of the systematics of insects, via molecular-based systematics.

Earth's species

-around 70% of all known species on earth are arthropods --75% of those are insects

Jointed legs

-as adults, insects have six legs (3 pair) -located on the middle section (the thorax) of the body -locomotory organ

Entomology

-basic and applied science

Scientific Name

-combination of the genus and species epithet

Applied science

-crop protection, freshwater bioassessment, forest entomology, etc.

Who cares about insects?

-everyone -scientists, teachers, veterinarians, pest control operators, farmers, crime-scene investigators

Tagmosis

-grouping of segments into a functional morphological unit

Insects (and arthropods)

-have segmented bodies

Why study bugs?

-insects can powerfully shape human existence through destructive interactions -Top four reasons -1. insects spread diseases to us -2. insects eat our crops -3. insects eat our stored food -4. insects main and kill our livestock (and pets)

Trachea

-insects exchange oxygen and carbon dioxide between their tissues and the air by a system of air-filled tubes

Numbers

-intvertebrates -1.4 million -vertebrates -62,000 -plants -321,000

Eyes

-located on the head of the insects -two kinds of eyed --simple --compound

Wings

-most adults have 2 pairs -forewings -hindwings -some insects are wingless --silverfish --fleas --some termites --ants -flying organs

Greek entomos

-notched segment

Spiracles

-on the exoskeletons to allow air to enter the trachea

Basic research

-physiology, biochemistry, structure, taxonomy, life histories

Insects central to our (human) well being

-pollination -insect-derived foods -insect's recycling efforts (dead things) -insect derived products (shoe and furniture polish)

Systematics

-seeks to determine the relatedness of different life forms -makes extensive use of fossil records along with biological features of extant species

Entomological Society of America

-standardized the common names

Radial symmetry

-symmetry about a central axis- like a starfish

Exoskeleton

-the hard, shell-like covering on the outside of the body -the external skeleton -primarily made of CHITIN -used for protection -maintain internal homeostasis

The body of an adult insect is divided into three parts

-the head -the thorax -the abdomen

Taxonomy

-the science of classification

Entomology

-the study of insects

Phylogenetics

-the study of the evolutionary relations between organisms

Latin insectum or insectare

-to cut into pieces