Taxonomy, Systematics, and Organismal Diversity

Comprehensive vocabulary flashcards generated directly from lecture notes on taxonomy, systematics, prokaryotic and eukaryotic diversity, plant phyla, and animal morphological body plans.

Taxonomy

The science of describing, naming, and classifying living organisms and viruses.

Systematics

The study of biological diversity and the evolutionary relationships among organisms, both extinct and modern.

Taxon

Each group or level of classification within a hierarchical system.

Domain

The highest level of biological classification, which all of life belongs to, consisting of Bacteria, Archaea, and Eukarya.

Prokaryotic cells

Cells meaning 'before nucleus' that lack a nucleus and lack membrane-bound organelles.

Eukaryotic cells

Cells meaning 'true nucleus' that possess a well-defined nucleus, membrane-bound organelles, and an internal membrane system.

Binomial nomenclature

A two-word naming system proposed by Carolus Linnaeus in 1753 consisting of a capitalized genus name and a lower-case specific epithet, both of which are italicized or underlined.

Carolus Linnaeus

The individual who proposed the artificial two-word naming system known as binomial nomenclature in 1753.

Phylogeny

The evolutionary history of a species or a group of species.

Phylogenetic tree

A diagram that describes phylogeny, representing a hypothesis of evolutionary relationships among various species based on available morphological and genetic information.

Paraphyletic group

A group containing a common ancestor and some, but not all, of its descendants.

Monophyletic group (clade)

A taxon group or group of species consisting of the most recent common ancestor and all of its descendants.

Molecular systematics

The analysis of genetic data such as DNA, RNA, and amino acid sequences to identify and study genetic similarities and propose phylogenetic trees.

Kingdom Protista

The earliest eukaryotes in the fossil record, mostly microscopic and found in moist environments, functioning as a catch-all kingdom for organisms that do not fit into other kingdoms.

Algae

Plant-like protists comprising 10 groups that are mostly autotrophic and photosynthetic, ranging from unicellular to large multicellular organisms with cell walls.

Protozoans

Animal-like protists that are mostly heterotrophic, including tiny unicellular organisms like amoeba and paramecium.

Fungal-like protists

Protists, such as slime molds, that are mostly saprotrophic (absorb feeding) and mostly multicellular.

Mycelium

The body of a fungus, consisting of a compacted mass of tubular filaments called hyphae.

Hyphae

Tubular filaments that compact together to form the mycelium of a fungus.

Fruiting body

The site of spore production in fungi.

Bryophytes

Nonvascular plants lacking conducting tissues (xylem and phloem), reproducing by spores, and requiring external water for swimming sperm. like mosses, liverworts, hornworts

Pteridophytes

Vascular plants containing xylem and phloem that reproduce by spores, possess true roots, stems, and leaves, and require external water for reproduction.

Gymnosperms

Seed-producing vascular plants whose seeds are not enclosed in a structure, and which use a pollen tube to deliver sperm to the egg without requiring external water.

Angiosperms

Advanced vascular plants (Phylum Anthophyta) that produce flowers, fruits, and seeds enclosed in a vessel (fruit).

Hox genes

Clusters of genes found in all animals that determine the animal body layout.

Parazoans

Multicellular animals, such as sponges (Phylum Porifera), that lack specialized tissues or organs.

Eumetazoans

True multicellular animals possessing more than one type of tissue and organs.

Radiata

Radially symmetric eumetazoans that can be divided equally by a longitudinal plane through the central axis and possess two germ layers (diploblastic).

Bilateria

Bilaterally symmetric eumetazoans that can be divided along a single vertical plane to produce two halves, exhibiting cephalization and three germ layers (triploblastic).

Blastopore

The first embryonic opening that develops during gastrulation.

Protostome

An animal in which the blastopore becomes the mouth.

Deuterostome

An advanced group of animals in which the blastopore becomes the anus.

Coelom

A fluid-filled body cavity that cushions internal organs and enables their movement and growth independent of the body wall.

Eucoelomate (Coelomate)

An animal having a true coelom completely lined with mesoderm or mesoderm-derived tissue.

Pseudocoelomate

An animal with a body cavity that is only partially lined with mesoderm, such as rotifers and roundworms.

Acoelomate

An animal that lacks a body cavity and instead has mesenchyme tissue (stuffing), such as flatworms.

Invertebrates

Animals without a backbone (vertebral column), making up 95% of animal species, with fossil records dating to 1.2 billion years.