Phylum Porifera Overview

Questions and Answers

What distinguishes sponges from protozoans?

Sponges have a digestive tract.

Sponges are organized on the cellular level. (correct)

Sponges have well-defined tissues.

Sponges are unicellular.

What material are the spicules in Class Calcarea primarily made of?

Keratin

Calcium carbonate (correct)

Silica

Collagen

Which class of sponges contains silicious spicules that are usually 6-rayed?

Class Sclerosponeae

Class Demospongeae

Class Calcarea

Class Hyalospongia (correct)

Which of the following statements about sponges is false?

They possess well-defined organ systems. Signup and view all the answers

What type of internal skeleton might be found in Class Demospongeae?

Silicious or sponging fibers or both Signup and view all the answers

Which class of sponges is known to have a hard internal skeleton composed of aragonite?

Class Sclerosponeae Signup and view all the answers

Study Notes

Overview of Phylum Porifera

Comprises animals known as sponges, representing the simplest form of multicellular life.
Body organization on a cellular level, differing from unicellular protozoans, where one cell performs all life functions.
Body structure features a system of canals for water intake and waste expulsion.
Possesses a skeleton formed by spicules (hard structures) or spongin fibers, or a combination of both.
Lacks true tissues and a digestive tract, highlighting its simple anatomical structure.

Classes of Phylum Porifera

Class Calcarea
- Known as calcareous sponges.
- Characterized by spicules composed of calcium carbonate.
- Spicules can be one, three, or four-rayed.
Class Hyalospongia
- Referred to as glass sponges.
- Distinguished by siliceous spicules, typically featuring six rays.
Class Demospongeae
- Internal skeleton composed of silicious materials and/or spongin fibers.
Class Sclerosponeae
- Contains species with a hard internal skeleton, often made of aragonite.
- Represents diverse structural adaptations among various sponge species.

Description

Explore the fascinating world of Phylum Porifera, which consists of sponges – the simplest multicellular animals. This quiz covers the cellular structure, body organization, and the unique canal system used by sponges for water and nutrient exchange. Test your knowledge on these fundamental organisms!