Unit 6 - Arthropoda
mandibles
One of a pair of jaw-like feeding appendages found in myriapods, hexapods, and crustaceans.
book lungs
Organs of gas exchange in spiders, consisting of stacked plates contained in an internal chamber.
Arthropoda
Phylum that have jointed appendages, an exoskeleton, bilateral symmetry, and reproduce sexually; insects, arachnids, millipedes and cenitpedes, and crustaceans
chitin
a carbohydrate that forms part of the exoskeleton of arthropods and other organisms, such as insects, crustaceans, fungi, and some algae
social arthropods
live in large groups with typically one reproductive queen, haploid males and female workers with different jobs ex) bees, wasps, termites, ants
segments and jointed appendages are better for
locomotion
Arthropods are protostomes
mouth forms first in embryonic development
chelipods
pair of large grasping claws in crustaceans
chelicera
pair of mouthparts in chelicerates that contain fangs and are used to stab and paralyze prey in chelicerata (arachnids)
spiracles
small opening located along the side of the body through which air enters and leaves the body of many terrestrial arthropods
swimmerets
small paired appendages located on the ventral surface of the abdomen of crustaceans used for swimming or reproduction
Arthropods account for ____% of all species on Earth
75
Insects make up _____% of Arthropods
90
compound eyes
eyes that contain many lenses and are especially keen at sensing movement
arachnids
A member of a major arthropod group, Chelicerata, that includes spiders, scorpions, ticks, and mites. All members have four pairs of walking legs, two body sections and no antennae.
malpighian tubules
An excretory organ that is unique to insects, empties into digestive tract and removes nitrogenous wastes from the hemolymph, also plays a role in osmoregulation.
thorax
An insect's midsection, to which its wings and legs are attached.
complete metamorphosis
Growth to the adult stage from larval stage (often many) to a transformative pupa stage and finally into the adult form: egg --> larva --> pupa --> adult example: butterfly, fly, beetle
incomplete metamorphosis
Growth to the adult stage without a pupa phase (intermediate phase is called a nymph): egg --> nymph --> adult example: dragonfly, spider, lobster
Viviparous
Internally fertilized eggs develop inside the female body and derive nutrition from her directly. Female gives birth to live young. Ex) scorpions, humans, cows
Oviparous
Internally fertilized eggs develop into eggs that are laid and hatch outside the mother's body
Ovoviviparous
Internally fertilized eggs develop within the mother's body but derive nutrition from the yolk of the egg (not her body), hatch inside and are born alive
antennae
Sensory structures that are able to detect air movement, vibrations, and smells
Exoskeleton in crustaceans reinforced with
calcium
Disadvantage of exoskeleton
can't grow, must be shed
harm from arthropods
disease, bites, toxins, destroy crops
nervous system
dorsal brain at the front of the organism, connected to nerve ring around the digestive system with a ventral nerve cord
Disadvantage of ecdysis
exoskeleton is soft after making the organism vulnerable to predation
benefits to humans of arthropods
food source, pollination, production of honey, population control of other organisms
Podos (Greek)
foot
Arthropods are coelomates
have a body cavity
Arthron (Greek)
jointed
ecdysis
periodic shedding of the cuticle in arthropods or the outer skin in reptiles
Exoskeleton is always made of
protein and chitin
Advantage of exoskeleton
provides support and protection from water loss
cephalothorax
region of a crustacean and chelicerata formed by the fusion of the head with the thorax
jointed appendages
structures such as a legs, wings, or antennae that extend from the body wall of an arthropod and enable them to move and grasp objects
Chelicerata
sub-phylum of arthropods that includes spiders, scorpions, ticks, and horseshoe crabs
Crustacea
subphylum of arthropoda; crabs, lobsters, crayfish, and shrimp
Myriapoda
subphylum of arthropoda; many feet; millipedes and centipedes
Exoskeleton
supportive, non-living structure on the outside of the organism
abdomen
the hind section of an arthropods body that contains its reproductive organs and part of its digestive tract
tracheal tubes (tracheoles)
tiny tubes in insect body that deliver oxygen directly to metabolizing tissues
spinnerets
tubelike structures in a spider's abdomen that the spider uses to make silk threads