Chap 3: pp. 60-64

Myxozoans

Highly modified cnidarians, not protozoans, discussed in Chapter 6.

Amoeboid Protozoans

Formerly grouped as Sarcodina, now recognized as a diverse group with about 56,000 described species.

Monophyletic

A term indicating a group that includes an ancestor and all its descendants; neither Sarcodina nor flagellates are monophyletic.

Pseudopodia

Cytoplasmic extensions used by amoeboid protozoans for locomotion and feeding.

Contractile Vacuoles

Organelles present in amoeboid protozoans, particularly freshwater species, that help regulate water balance.

Asexual Reproduction

The primary mode of reproduction in amoeboid protozoans, mainly through binary or multiple fission.

Encystment

A survival strategy among amoeboid protozoans, allowing them to withstand unfavorable environmental conditions.

Amoebic Dysentery

A disease caused by Entamoeba histolytica, affecting over 500,000 people worldwide at any time.

Naked Amoebae

Free-living amoebae without a test, characterized by their ability to change shape and use pseudopodia for feeding.

Test-bearing Amoebae

Amoebae that secrete a protective covering or test, often found in soil and aquatic environments.

Slime Molds

Members of Eumycetozoa that exhibit both amoeboid and multicellular stages, often found in decaying vegetation.

Mastigamoebae

Organisms with both flagella and pseudopodia, indicating a close evolutionary relationship between amoeboid and flagellate forms.

Rhizaria

A group characterized by splender pseudopodia, proposed based on molecular data, including foraminiferans and radiolarians.

Foraminiferans

Marine protozoans with multi-chambered tests, primarily benthic, feeding on a variety of organic materials.

Reticulopodia

Branching pseudopodia of foraminiferans that form dense networks for food capture and locomotion.

Fossil Record

Foraminiferan tests are abundant in the fossil record, dating back to the Early Cambrian, with significant economic importance.