Transcript ARTHROPODS - Katy Independent School District

ARTHROPODS
Kingdom – Animalia
Phylum Arthropoda – “jointed foot”
Sub phyla:
Crustacea – crabs, crawfish, shrimp
ARTHROPODS
Kingdom – Animalia
Phylum Arthropoda – “jointed foot”
Sub phyla:
Chelicerata – horseshoe crab, spiders
ARTHROPODS
Kingdom – Animalia
Phylum Arthropoda – “jointed foot”
Sub phyla:
Uniramia – insects, centipedes, millipedes
ARTHROPODS
Kingdom – Animalia
Phylum Arthropoda – “jointed foot”
Sub phyla:
Trilobita – ancestor of today’s arthropods
extinct
Basic Characteristics
1. Segmented bodies divided into segments fused into 2 or 3
larger body regions
Basic Characteristics
1. Jointed appendages – for sensing, eating, reproduction,
moving, defending
Basic Characteristics
1. Exoskeleton – outside skeleton
1. Made of chitin – type of carbohydrate
2. Hardened for protection
3. Limits the size because it has to molt to grow
2. Bilateral symmetry
BODY SYSTEMS
• Nervous system
– Ventral nerve cord and brain
– Has ganglia in each segment
– Most have compound eyes
• Circulatory system
– Open system – no vessels to enclose blood
• Respiratory system
– Gills in aquatic animals
– Tracheal tubes in terrestrial animals
CRUSTACEANS
• Body regions – Cephalothorax – head and thorax are fused
• Most appendages are attached here
• Covered by a hardened shell of chitin (carapace)
– Abdomen – long, narrow tail region
• Segmented
• Have swimmerets
CRUSTACEANS
• Body systems
– Respiratory
• Feathery gills in the thorax – connected to walking legs to
create water flow over the gills
– Excretory
• Green gland located in the head extracts nitrogenous
wastes from the blood and maintains proper water and ion
amounts in the body
– Reproductive
• Sexual
• Eggs are fertilized as they pass through the gonopore
• Swimmerets hold the fertilized eggs
CHELICERATES
• Body regions
– Cephalothorax
– Abdomen
• Do not have sensory antennae like other arthropods
• Most have simple eyes, not compound
• All have appendages called chelicerae
– Modified pincers or fangs for killing prey
• Most are terrestrial except for the horseshoe crab
• Have simple and compound eyes
• Obtain oxygen through book gills
• Includes the Class Arachnida – spiders, mites & ticks
UNIRAMIANS
• Includes insects, centipedes and millipedes
• Have 3 body regions
– Head
– Thorax
– Abdomen
• Have compound eyes
• Have malphigian tubules to excrete waste
• Have tracheal tubes for respiration
TRILOBITA
• Extinct ancestors to today’s arthropods