Echinoderms: Characteristics, Body Structure, and Development

What is the function of tube feet in echinoderms?

Which class of echinoderms is characterized by a globular body and movable spines?

What is the process by which echinoderm larvae settle on the ocean floor and undergo transformation?

What is a distinctive feature of the echinoderm skeleton?

How do echinoderm adults reproduce?

Which echinoderm class is known for its feathery arms and stalked body?

What is the main characteristic of an echinoderm's body structure?

What is the primary function of an echinoderm's water vascular system?

Which of the following is NOT a type of echinoderm?

What is the primary source of food for echinoderms?

What is the role of echinoderms in marine ecosystems?

How do echinoderms move?

What is the typical body shape of echinoderms?

What is the function of the anus in echinoderms?

Which of the following classes of echinoderms includes sea stars and starfish?

What is the process by which echinoderm larvae develop?

Characteristics

Echinoderms are a phylum of marine animals
Characterized by:
- Radial symmetry (body organized around a central axis)
- Calcite skeleton
- Water vascular system (unique system of fluid-filled vessels)
- Tube feet (used for movement, feeding, and respiration)

Body Structure

Body shape varies among classes, but typically includes:
- Central body (disc or sphere)
- Arms or rays ( extensions of the body)
- Mouth and anus on opposite sides of the body
Skin and muscles are thin, allowing for flexibility

Classes of Echinoderms

Asteroidea (Starfish or Sea Stars)
- Characterized by five-armed body shape
- Feed on clams, mussels, and snails
Ophiuroidea (Brittle Stars)
- Characterized by long, slender arms
- Feed on small invertebrates and organic matter
Echinoidea (Sea Urchins)
- Characterized by globular body and movable spines
- Feed on algae and small invertebrates
Holothuroidea (Sea Cucumbers)
- Characterized by elongated, soft body
- Feed on organic matter and small invertebrates
Crinoidea (Sea Lilies)
- Characterized by feathery arms and stalked body
- Feed on small invertebrates and organic matter

Development and Reproduction

Echinoderms undergo indirect development (larval stage)
Larvae settle on the ocean floor and undergo metamorphosis
Adults reproduce sexually, releasing gametes into the water column
Fertilization occurs externally, and larvae develop from zygotes

This quiz covers the characteristics, body structure, and development of echinoderms, a phylum of marine animals. Learn about the different classes of echinoderms, including starfish, brittle stars, sea urchins, sea cucumbers, and sea lilies. Understand their unique features, feeding habits, and life cycles.