Lecture 24: Arthropoda I Flashcards
Phylum Arthropoda traits
Most species-rich phylum of any organism
Open circ system
Segmented
Jointed appendages
Cephalization?
Nervous system becomes concentrated towards head.
Tagmatization?
Segmented body & jointed appendages arranged into functional units w/ specialized function
Arthropod groups?
Trilobita Crustacea Myriapoda Chelicerata Hexapoda
Crustacea?
Crabs, lobsters and shrimp Mostly marine Compound eyes and two antenna Cephalothorax Carapace
Cephalothorax?
Head and thorax merged
Carapace
Shields lateral and dorsal sides as well as abdomen
Thoracic limbs?
Locomotion in crustacean
Abdominal limbs?
Filter feeding, carrying eggs, swimming in crustacean
Crustacean exoskeleton is strengthened with?
Calcium carbonate
Aquatic crustacea use ___, terrestrial use ___?
gills, trachae
Crustacean life?
Separate sexes
Variable
Sperm transfer via copulaton
Ecology?
Diverse
Some filter feed
Some predatory (feed on fish)
Some are commensals or parasites of vertebrates or invertebrates
Hexapod and myriapod similarities?
One pair of antennae
Mandibles
Trachae for gas exchange
Hexapods traits?
6 legs
Hexapod morphology?
Head with one pair of antennae Thorax with 3 pairs of legs Abdomen Cerci (segmented appendages) Compound eyes some have ocelli (simple eyes)
Incomplete metamorphosis?
Grasshoppers and dragonflies
Nymphs share morphology of adults but grow wings over time
Complete metamorphosis?
Wings develop all at once in a pupa
Morphology of adult is different
Moulting in hexapods
Shedding all ectodermally-derived cuticle
Hexapoda sex?
Different sexes
Collembolans and apterygote insects transfer sperm indirectly
Pterygotes copulate
Importance of hexapods?
Polliation
Important decomposers
Predators, herbivores, vectors, and parasites
