Fossil Classification Flashcards

Questions and Answers

What is Phylum PORIFERA?

Marine bivalve, filter feeding, bilateral symmetrical

Aquatic, sessile, colonial

Sponges, single or colonial, composed of siliceous or calcareous spicules that fuse together (correct)

5 fold symmetry with body composed of plates with spines

What bodies are composed of two layers enclosing a central cavity?

Phylum CNIDARIA

What class do corals belong to?

Class ANTHOZOA

What distinguishes Order TABULATA?

Individual corallites partitioned by transverse tabulae, no septa. Signup and view all the answers

What defines Order RUGOSA?

Four primary septa, secondary ones evolve during maturity. Signup and view all the answers

How are septa arranged in Order SCLERACTINIA?

In sets of six or multiples of six. Signup and view all the answers

What is Phylum BRYOZOA known for?

Aquatic, sessile, colonial Signup and view all the answers

What characterizes Phylum BRACHIOPODA?

Marine bivalve, filter feeding, bilateral symmetrical Signup and view all the answers

What defines Phylum MOLLUSCA?

Diverse group with a muscular foot, usually with hard shell. Signup and view all the answers

What is Class GASTROPODA characterized by?

Trochoidal spiral Signup and view all the answers

What describes Class BIVALVIA?

Bivalve with top and bottom valve mirror images of each other. Signup and view all the answers

What defines Class CEPHALOPODA?

Bilaterally symmetrical, has head and tentacles. Signup and view all the answers

What is the characteristic of Subclass NAUTILOIDEA?

Segmented shell, uncoiled or planispiral. Signup and view all the answers

What distinguishes Subclass AMMONOIDEA?

Segmented shell, highly ornate sutures. Signup and view all the answers

What is unique about Subclass COLEOIDEA?

Shell is reduced or missing, squid, belemnoid. Signup and view all the answers

What describes Phylum ANNELIDA?

Segmented worm - forms burrows. Signup and view all the answers

What is a defining feature of Phylum ARTHROPODA?

Segmented exoskeleton and jointed limbs. Signup and view all the answers

What is characteristic of Class TRILOBITA?

3 lobed body, bilaterally symmetrical. Signup and view all the answers

What defines Class CIRRIPEDIA?

Fused head and body (barnacles). Signup and view all the answers

What characterizes Phylum ECHINODERMATA?

5 fold symmetry with body composed of plates with spines. Signup and view all the answers

What is unique about Subphylum CRINOZOA?

Attached to sea floor by tubular, segmented stem. Signup and view all the answers

What does Class CRINOIDEA have?

Long stem and long brachioles (arms) on calyx (head). Signup and view all the answers

What characterizes Subphylum BLASTOZOA?

Attached to the sea floor by tubular, segmented stem. Signup and view all the answers

What distinguishes Class BLASTOIDEA?

"Blastoids", has short stem. Signup and view all the answers

What defines Class RHOMBIFERA?

"Cystoids", primitive relatives of blastoids. Signup and view all the answers

What does Subphylum ECHINOZOA include?

Sea urchins - motile, able to move, five plates. Signup and view all the answers

What characterizes Class ECHINOIDEA?

Sea urchins, sea biscuits, sand dollars. Signup and view all the answers

What is unique about Subphylum ASTEROZOA?

Motile and star-shaped. Signup and view all the answers

What does Class ASTEROIDEA represent?

Star fish (no central body). Signup and view all the answers

What characterizes Class OPHIUROIDEA?

Brittle star (has distinct central body). Signup and view all the answers

What are Unaltered Body Fossils?

Complete body of organism is intact with all original hard parts, soft parts, and chemical composition. Signup and view all the answers

What are Altered Body Fossils?

Complete body of organism is intact but all parts have been altered from their original chemical composition. Signup and view all the answers

What is recrystallization?

A metamorphic process that occurs under intense temperature and pressure. Signup and view all the answers

What occurs during replacement?

The shell, bone or other tissue is replaced with another mineral. Signup and view all the answers

What is permineralization?

A process of fossilization in which mineral deposits form internal casts of organisms. Signup and view all the answers

What are molds?

A cavity left behind when the organic material is dissolved away. Signup and view all the answers

What are casts?

A finely preserved representation of the surface features of the organism. Signup and view all the answers

What is carbonization?

Outline of organism in carbon residue. Signup and view all the answers

What are trace fossils?

Any identifiable mark left by a living organism. Signup and view all the answers

What are tracks in trace fossils?

Separate footprints. Signup and view all the answers

What are trails in trace fossils?

A continuous 'dragging' mark. Signup and view all the answers

What are burrows in trace fossils?

A hole dug for means of residence or passage. Signup and view all the answers

What are coprolites?

Preserved feces. Signup and view all the answers

Study Notes

Phylum PORIFERA

Comprises sponges, either single or colonial.
Built from siliceous or calcareous spicules that fuse together.

Phylum CNIDARIA

Characterized by bodies with two layers surrounding a central cavity.
Includes class ANTHOZOA with suborders TABULATA, RUGOSA, and SCLERACTINIA.

Class ANTHOZOA

Encompasses corals and various orders such as TABULATA, RUGOSA, and SCLERACTINIA.

Order TABULATA

Features corallites partitioned by transverse tabulae and lacks septa.
Extinct order within phylum CNIDARIA and class ANTHOZOA.

Order RUGOSA

Identified by four primary septa, with secondary septa developing as they mature.
This order is also extinct and part of phylum CNIDARIA and class ANTHOZOA.

Order SCLERACTINIA

Contains corals with septa arranged in sets of six or multiples of six.
Part of phylum CNIDARIA and class ANTHOZOA.

Phylum BRYOZOA

Comprises aquatic, sessile, and colonial organisms.

Phylum BRACHIOPODA

Marine bivalves that filter feed; exhibit bilateral symmetry.

Phylum MOLLUSCA

A diverse group having a muscular foot, often with a hard unsegmented shell.
Main classes include GASTROPODA, BIVALVIA, CEPHALOPODA, subdivided into NAUTILOIDEA, AMMONOIDEA, and COLEOIDEA.

Class GASTROPODA

Features a distinct trochoidal spiral shape.
Belongs to phylum MOLLUSCA.

Class BIVALVIA

Represents bivalves where the top and bottom valves are mirror images.
Associated with phylum MOLLUSCA.

Class CEPHALOPODA

Known for a bilaterally symmetrical body with a head and tentacles.
Contains subclasses NAUTILOIDEA, AMMONOIDEA, and COLEOIDEA.

Subclass NAUTILOIDEA

Characterized by a segmented, uncoiled or planispiral shell with simple sutures.

Subclass AMMONOIDEA

Features a segmented, ornate shell with intricate sutures.

Subclass COLEOIDEA

Shell is greatly reduced or absent, which includes modern cephalopods like squid and belemnoids.

Phylum ANNELIDA

Represents segmented worms equipped for burrowing.

Phylum ARTHROPODA

Distinguished by a segmented exoskeleton, jointed limbs, and bilateral symmetry.
Includes superclass TRILOBITOMORPHA (class TRILOBITA) and superclass CRUSTACEA (class CIRRIPEDIA).

Class TRILOBITA

Known as trilobites with a tripartite body structure and bilateral symmetry.

Class CIRRIPEDIA

Comprises barnacles characterized by a fused head and body.

Phylum ECHINODERMATA

Exhibits five-fold symmetry and a body formed from plates with spines.
Contains various subphyla including CRINOZOA, BLASTOZOA, and ECHINOZOA.

Subphylum CRINOZOA

Includes sessile organisms attached to the sea floor by a tubular, segmented stem.
Calyx may separate post-mortem due to decay.

Class CRINOIDEA

Recognized by a long stem and numerous brachioles or arms on the calyx.

Subphylum BLASTOZOA

Sessile, attached organisms with a tubular, segmented stem and fused theca plates, preserving head integrity after death.

Class BLASTOIDEA

Blastoids with a short stem and symmetrical arrangement of plates and arms.

Class RHOMBIFERA

Primitive relatives of blastoids with irregular plate arrangement.

Subphylum ECHINOZOA

Comprises sea urchins that are motile and feature five plates.

Class ECHINOIDEA

Represents sea urchins, sea biscuits, and sand dollars.

Subphylum ASTEROZOA

Characterized by motility and a star-shaped morphology.

Class ASTEROIDEA

Known as starfish, lacking a central body.

Class OPHIUROIDEA

Includes brittle stars with a distinct central body.

Unaltered Body Fossils

Fossils where the complete organism is preserved, retaining all original hard and soft parts.

Altered Body Fossils

These fossils maintain the original body form but have undergone changes in chemical composition.
Methods include recrystallization, replacement, and permineralization.

Recrystallization

A metamorphic process resulting in new crystal structures due to high temperature and pressure.

Replacement

Occurs when organic tissues, such as shells or bones, are substituted with other minerals.

Permineralization

A fossilization process where mineral deposits create internal casts of organisms.

Molds

Cavities leftover when organic materials dissolve, retaining only external impressions.

Casts

Detailed representations of an organism's surface features formed from mineralization.

Carbonization

Results in an outline of organisms preserved in carbon residue.

Trace Fossils

Identifiable marks made by organisms, including tracks, trails, burrows, and coprolites.

Tracks (Trace Fossils)

Represent footprints of organisms.

Trails (Trace Fossils)

Continuous marks created by dragging movement.

Burrows (Trace Fossils)

Holes made for habitation or movement.

Coprolites (Trace Fossils)

Preserved fecal matter, providing insights into diet and behavior.

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Description

Test your knowledge on various fossil classifications with these flashcards. Covering phyla such as Porifera and Cnidaria, this quiz provides essential definitions and classifications for each group. Perfect for students of paleontology and biology.