Chaetognaths, Echinoderms, and Hemichordates

These flashcards cover key concepts related to the lecture on Chaetognaths, Echinoderms, and Hemichordates, focusing on their characteristics, ecological roles, and evolutionary significance.

What defines deuterostomes during development?

In deuterostomes, the blastopore becomes the anus.

What is the primary evolutionary trait of Phylum Chaetognatha?

Chaetognaths, or arrow worms, are pelagic marine predators with a debated evolutionary position.

List three characteristics of Echinodermata.

Echinoderms have a unique water-vascular system, pentaradial symmetry, and a complete digestive system.

What are the key ecological roles played by Echinoderms?

Echinoderms like sea stars act as top predators, feeding on mollusks, crustaceans, and other invertebrates.

What is a notable feature of the class Asteroidea?

Sea stars can regenerate lost parts after casting off injured arms.

What distinguishes Phylum Hemichordata from other phyla?

Hemichordates contain gill slits and a structure called stomochord, which is not homologous to the notochord of chordates.

What is the significance of pharyngeal gill slits in chordates?

Pharyngeal gill slits lead from the pharyngeal cavity to the outside and give rise to various structures in tetrapods.

What is the function of the swim bladder in bony fishes?

The swim bladder helps in buoyancy and allows fish to maintain depth without muscular effort.

How do amphibians adapt to a terrestrial lifestyle?

Amphibians have developed adaptations like stronger vertebral columns and jointed limbs to support their bodies on land.

What is one notable reproductive characteristic of amphibians?

Amphibians must reproduce in water or moist areas as their eggs are aquatic.