Protosomes- Questions

What defines a protosome?

mouth develops first from blastopore

What kind of cleavage do protostomes have?

spiral and determinate cleavage

What are the two main groups of protosomes?

Lophotrochozoa and Ecdysozoa

What is a lophophore

a ciliated feeding structure found in some lophotrochozoans

What is a trochophore larva?

a ciliated larval form

What are four major Lophotrochozoa phyla?

Platyhelminthes, Roifera, Annelida, Mollusca

What is unique about flatworms?

acoelomates with simple organ systems and no circulatory system

What is parthenogenesis?

asexual reproduction where females produce offspring without fertilization

What key features distinguish annelids?

segmented bodies and a true coelom

What are the three main parts of a mollusk’s body?

foot, mantle, visceral mass

What is the radula used for?

scraping or cutting food

What is ecdysis?

molting of the exoskeleton for growth

Which two phyla are ecdysozoans?

Nematoda and Arthropoda

What are nematodes commonly known as?

roundworms

What is the arthropod exoskeleton made of?

Chitin

What are the four main groups of arthropods?

Chelicerates, Myriapods, Crustaceans, Insects

What allows insects to occupy diverse habitats?

wings, metamorphosis, and specialized mouthparts

Which arthropod group is the most species-rich?

insects

What is metamorphosis?