BIO Exam 4: Ecdysozoans II: Crustaceans and Insects lecture

What are the 2 critical innovations for the Phylum Arthropoda?

chitinous exoskeleton with jointed appendages; mandibles

What species are in Subphylum Myriapoda?

millipedes and centipedes

What are the differences between millipedes and centipedes?

• Millipedes: have 4 legs per segment and are herbivorous

• Centipedes: have 2 legs per segment and are carnivorous

What species does Subphylum Crustacea include?

lobsters, shrimp, crabs, barnacles

What is the cuticle exoskeleton of the Subphylum Crustacea made out of?

calcium

True or false: The Subphylum Crustacea have mandibles

True

What is the form and function of the Subphylum Crustacea?

Two pairs of antennae, thorax and abdomen, carapace

What is a carapace?

a hard dorsal shield or exoskeleton

What is the function of the appendage specialization of swimmerets?

modified for reproduction

What is the function of the appendage specialization of uropods?

backward movements

What is the function of the appendage specialization of mandibles called maxilla?

modified for feeding

What is the function of the appendage specialization of cheliped?

modified for defense

What body coelom do the Subphylum Crustacea have?

hemocoel

Do the species in Subphylum Crustacea have an open or closed circulatory system?

open

True or false: the Subphylum Crustacea must molt or ecdysis to grow?

True

How does molting work?

The process of breaking down old cuticle layers and secrete new ones.

• the older cuticle becomes thin

• the epidermis undergoes cell division digesting the old cuticle by secreting enzymes

• a new cuticle forms inside the old

• the old cuticle splits, the animal swells with water stretching to the new larger shell size

What are two unique characteristics of the Subphylum Crustacea reproduction?

specialized egg brooding and metamorphosis (indirect development)

What type of larvae stage do all Crustaceans go through either embryonically or free-living?

Nauplius

What evolutionary innovation first appeared in Arthropods, and is a characteristic of the most successful of all animal groups?

jointed appendages

What are the 2 critical innovations of the Subphylum’s Chelicerata and Myriapoda in the Phylum Arthropoda?

chitinous exoskeleton with jointed appendages

What 1 critical innovations of the Subphylum’s Myriapoda, Hexapoda, and Crustacea in the Phylum Arthropoda?

Mandibles

What 1 critical innovation of the Subphylum’s Crustacea and Hexapoda are in Phylum Arthropoda?

All head appendages expect the 1st antennae used for feeding sometime in life

What class is in Subphylum Hexapoda?

Class Insecta

What are some characteristics of the Subphylum Hexapoda?

most abundant and diverse arthropod; economic importance

What are the defining traits of Class Insecta?

3 tagmata, one pair of antennae and 3 pairs of walking legs, wings, tracheae, mandibles

What 3 tagmata make up the Class Insecta?

head, thorax, abdomen

What type of respiratory system does the Subphylum Hexapoda have?

Tracheal system

What tubules are used for excretion in the Subphylum Hexapoda?

Malpighian tubules

What are some form and function characteristics of the Subphylum Hexapoda?

well-developed sense organs (most with compound eye and hair-like structures called sensilla), complete digestive system, food resource variation, mouth part linked to diet

What are the defining reproduction features of the Subphylum Hexapoda?

Either Holometabolus or Hemimetabolous dramatic metamorphosis; diapause

What is Holometabolus?

insects undergo complete metamorphosis, all 4 stages

What is Hemimetabolus?

insects undergo incomplete metamorphosis, 3 stages

What is diapause?

seasonal dormancy

What are the wings of insects composed of?

cuticle

What type of flight muscles do insects have?

direct and indirect

How many pairs of wings do insects typically have?

2

What is Eusociality in insects?

animals that live in highly organized social groups: cooperative brood care, overlapping generations, division of labor (reproductive and non-reproductive)