BIO Exam 4: Ecdysozoans I: Nematodes and Arthropods I lecture

What is the critical innovation of ecdysozoans?

ecdysis

What 2 phyla are apart of ecdysozoans?

Nematodes and Anthropods

Are ecdysozaons protosomes? What cleavage?

Yes; spiral cleavage

What is ecdysis?

animals must shed their non-living exoskeleton in order to grow

What is the exoskeleton made of in ecdysozoans?

chitin and proteins

What are the characteristics of the ecdysozaon’s exoskeletons?

both hard and flexible, rapid locomotion, waterproof, molting

What are the characteristics of the Phylum Nematoda?

mostly parasitic, small, crop damage, carry disease to mammals and humans

What is the embryonic development for the Phylum Nemotoda?

They are triploblastic, pseudocoelomate, and protostomes

What does triploblastic mean?

have all 3 tissues: ectoderm, mesoderm, and endoderm

What does pseudocoelomate mean?

false coelom, partially lined with mesoderm

What are the form & function characteristics of the Phylum Nemotoda?

tube-within-a-tube body, pseudocoel, syncytial epidermis (support), and longitudinal muscles (thrashing movement)

What does the form of the pseudocoel promote?

freedom of movement, hydrostatic skeleton

True or false: The Phylum Arhropoda the most diverse group of animals?

True

What 3 large and 1 small subphyla is in the Phylum Arthropoda?

1. Chelicerata (spiders, scorpions, ticks)

2. Crustacea (crabs, shrimp, lobsters)

3. Hexapoda (insects)

4. Myriapoda (smaller group)

What are the defining traits of the Phylum Arhropoda?

exoskeleton, segmentation, jointed appendages, hemocoel, cephalization, sensory systems, respiration via trachea or gills

What is the embryonic development of the Phylum Arthropoda?

triploblastic, coelomate, protostomes (schizocoely coelom, coelom arises from split mesodermal tissue)

What is tagmata?

the fusing of segments to form functional groups

What are some examples of tagmata functional groups?

cephothorax and abdomen, head and trunk

What a jointed appendages?

each segment may have one pair of appendages: legs, mouthparts, wings

True or false: Wings are modified appendages

False, wings are cuticular outgrowths

What are 2 characteristics of jointed appendages?

specialized division of labor and efficient locomotion

What is the difference between Chelicerae and Mandibles mouthparts?

• Chelicerae: hollow mouthpart containing venom glands injected into prey or predators

• Mandibles: mouthpart used to grasp, crush, or cut food or to defend against predators

What 2 respiratory systems does the Phylum Arhtrpodoa have?

aquatic species has gills and terrestrial species have a tracheal system

How does the tracheal system in the Phylum Arhtropoda work?

Air enters spiracles (pores) delivering air directly to cells and tissues

How many pairs of appendages does the Subphylum Chelicerata have? What is the breakdown?

six:

• 4 pairs of walking legs

• 1 pair of chelicerae (fangs)

• 1 pair of pedipalps

What 2 tagmata make up the body of Subphylum Chelicerata?

cephalothorax and abdomen

What class is in Subphylum Chelicerata?

Class Arachnida; spiders, scorpions, ticks and mites

What are the characteristics of the Class Arachnida?

predatory with fangs, stingers, and poison glands; predigest food before consuming

What type of unique lungs do spiders have?

book lungs - provide a large surface area for gas exchange by opening the exoskeleton

What specialized excretory tubules do spiders have?

Malpighian tubules

What do Malpighian tubules do?

aid in water retention

What are characterisitics of spiders?

• 8 simple eyes

• hair-like sensory setae to detect vibrations

• spinnerets (silk glands)

What is the scorpion body form tagmata?

short cephalothorax, preabdomen, and postabdomen (tail with stinger)

True or false: Scorpions have pedipalps

True