PHYLUM ARTHROPODA
GENERAL CHARACTERISTICS
- arthro means joint and pod means foot
- largest phylum
- bilateral symmetry
- open circulatory system
- well-developed nervous system
- wide range of habitat and diet
- most are equipped for defense against enemies
DISTINCT CHARACTERISTICS
segmented body organization
- differentiated into head, thorax, abdomen (often cephalothorax)
- body segments called somites or metameres
- with pairs of segmented appendages specialized for different tasks
Hard chitinous exoskeleton
- skeleton and support
- external armor for protection against harsh external conditions
Molting (ecdysis) of exoskeleton for growth
- radical changes in body plan in between molts
- constraints in size
- important in paleontology: development in growth can be fossilized
, ANNELIDA SIMILARITIES ARTHROPODA
-absence of -bilaterally -exoskeleton
exoskeleton symmetrical
-specialization
-no -segmentation of segments
specialization
-well- -jointed
-absence of developed
-compound
joints nervous
eyes
system
MODE OF LIFE
HABITAT
- Terrestrial
- Freshwater
- Marine
- Air
- Extreme Environments
FEEDING MECHANISM
- Parasites
- Predators
- Herbivores
- Carnivores
- Scavengers
REPRODUCTION
- A few are hermaphroditic
- most have separate sexes
- most lay eggs
- sexual reproduction
o eggs are fertilized by male
o internal or external
- asexual reproduction
o parthenogenesis: embryo develop without fertilization
- metamorphosis
o pronounced changes in body form after the egg hatches
GENERAL CHARACTERISTICS
- arthro means joint and pod means foot
- largest phylum
- bilateral symmetry
- open circulatory system
- well-developed nervous system
- wide range of habitat and diet
- most are equipped for defense against enemies
DISTINCT CHARACTERISTICS
segmented body organization
- differentiated into head, thorax, abdomen (often cephalothorax)
- body segments called somites or metameres
- with pairs of segmented appendages specialized for different tasks
Hard chitinous exoskeleton
- skeleton and support
- external armor for protection against harsh external conditions
Molting (ecdysis) of exoskeleton for growth
- radical changes in body plan in between molts
- constraints in size
- important in paleontology: development in growth can be fossilized
, ANNELIDA SIMILARITIES ARTHROPODA
-absence of -bilaterally -exoskeleton
exoskeleton symmetrical
-specialization
-no -segmentation of segments
specialization
-well- -jointed
-absence of developed
-compound
joints nervous
eyes
system
MODE OF LIFE
HABITAT
- Terrestrial
- Freshwater
- Marine
- Air
- Extreme Environments
FEEDING MECHANISM
- Parasites
- Predators
- Herbivores
- Carnivores
- Scavengers
REPRODUCTION
- A few are hermaphroditic
- most have separate sexes
- most lay eggs
- sexual reproduction
o eggs are fertilized by male
o internal or external
- asexual reproduction
o parthenogenesis: embryo develop without fertilization
- metamorphosis
o pronounced changes in body form after the egg hatches
