Biological Diversity of Life: Invertebrates and Vertebrates

A comprehensive set of vocabulary flashcards covering key terms related to invertebrates, vertebrates, and their evolution within the Biological Diversity of Life.

Invertebrates

Animals without a backbone.

Vertebrates

Animals with a backbone.

Mollusks

Soft-bodied invertebrates that often have a shell.

Arthropoda

Phylum of invertebrate animals having an exoskeleton, a segmented body, and paired jointed appendages.

Mammals

Warm-blooded vertebrates with hair, fur, and mammary glands.

Birds

Warm-blooded vertebrates characterized by feathers, wings, and an beak.

Reptiles

Cold-blooded vertebrates that lay eggs and have scales.

Amphibians

Cold-blooded vertebrates that usually start life in water and undergo metamorphosis.

Platyhelminthes

Phylum of flatworms, characterized by their flattened bodies.

Coelomates

Organisms with a true coelom (body cavity).

Acoelomate

Organisms without a body cavity.

Rotifers

Microscopic, multicellular organisms commonly found in freshwater.

Nematoda

Phylum of roundworms, which are mostly microscopic.

Echinodermata

Phylum that includes starfish and sea urchins, characterized by their radial symmetry.

Annelida

Phylum of segmented worms.

Mollusca

Phylum that includes snails, clams, and octopuses.

Psuedocoelomates

Organisms with a body cavity that is not lined with mesoderm.

Diploblastic

Organisms with two germ layers: ectoderm and endoderm.

Triploblastic

Organisms with three germ layers: ectoderm, mesoderm, and endoderm.

Bilateral symmetry

Organisms with a symmetrical body plan that can be divided into mirror-image halves.

Radial symmetry

Organisms that have symmetry around a central axis.

Chordata

Phylum that includes all vertebrates and some invertebrates like tunicates and lancelets.

Protochordates

Invertebrate chordates, such as cephalochordates and urochordates.

Notochord

A flexible rod-like structure that is present in embryos of all chordates.

Dorsal nerve cord

Nerve cord that runs along the back of some animals, including chordates.

Gill slits

Anatomical structures present in the embryos of all chordates.

Amniotic eggs

Eggs that have a protective shell and membranes that prevent water loss.

Craniates

Animals with a skull; includes all vertebrates and some invertebrates.

Gnathostomes

Jawed vertebrates, which evolved from jawless ancestors.

Actinopterygii

Class of ray-finned fishes.

Sarcopterygii

Class of lobe-finned fishes, which gave rise to land vertebrates.

Osteichthyes

Class of bony fishes.

Chondrichthyes

Class of cartilaginous fishes like sharks and rays.

Tetrapoda

Superclass that includes all vertebrates with four limbs.

Amniotes

Group of vertebrates that lay amniotic eggs.

Monotremes

Egg-laying mammals, such as the platypus.

Marsupials

Mammals that give birth to underdeveloped young that continue to develop in a pouch.

Eutherians

Placental mammals that give birth to fully developed young.

Primates

Order of mammals that includes humans, monkeys, and apes.

Anthropoids

Group of primates that includes monkeys and apes.

Hominins

Group of species that includes modern humans and our closest ancestors.

Evolution

Changes in the heritable traits of biological populations over successive generations.

Cambrian explosion

Rapid diversification of life forms that occurred around 540 million years ago.

Mass extinction

A widespread and rapid decrease in the biodiversity on Earth.

Theropods

A group of bipedal dinosaurs from which modern birds are descended.

Extinction event

A period in time when a significant number of species die out.

Convergent evolution

The process through which unrelated organisms independently evolve similarities.

Fossil record

The collection of fossils which provides evidence about the history of life on Earth.

Habitat

The natural environment in which an organism lives.

Skeletal remains

The bones left over after an organism has died.

Epidermal structures

Outermost layer of cells, often modified for protection or locomotion.

Behavioral adaptations

Actions animals take to survive in their environments.

Geologic time scale

A system of chronological dating that relates geological strata to time.

Phylogenetics

The study of the evolutionary history and relationships among individuals or groups.

Pangea

The supercontinent that existed during the late Paleozoic and early Mesozoic eras.

Endotherm

An organism that maintains its body temperature through internal processes.