Diversity of Living Things

Flashcards covering the diversity of living things, including phylogenetic trees, classification systems, and characteristics of different kingdoms.

Phylogeny

The evolutionary relatedness of species.

Phylogenetic Trees

Diagrams used to show evolutionary relationships among species and groups.

Clade

A taxonomic group that includes all the descendants of a common ancestor.

Nodes

Represent the most recent common ancestor of a clade.

Finding the most recent common ancestor

Starting at the branch ends carrying the two species of interest and “walk backwards” in the tree until we find the point where the species’ lines converge.

Biological classification

A hierarchy from general groups (such as domains) down to specific groups (genus and species).

The Three Domains of Life

Bacteria, Archaea, and Eukarya.

Six Kingdoms

Eubacteria, Archaebacteria, Protista, Plantae, Fungi, and Animalia.

Prokaryotic Cell

Small (1-10 µm), single chromosome, DNA circular, not bounded by nuclear membrane, division by fission, asexual reproduction common.

Eukaryotic Cell

Large (10-100 µm), many chromosomes, DNA in nucleus bounded by nuclear membrane, division by mitosis and meiosis, sexual reproduction common.

Binomial Nomenclature

The “two-word” naming system is a combination of the genus name and the species name to uniquely identify each organism.

Kingdom Archaea

Unicellular, prokaryotes, cell membrane contains unusual lipids and proteins. Autotrophs or heterotrophs.

Thermophiles

Heat-loving; found in hot springs and hydrothermal vents.

Methanogens

Convert CO2 into methane; live in oxygen-free environment.

Halophiles

Salt-loving; need high salt concentration to survive.

Kingdom Bacteria

Unicellular, prokaryotes, some move (flagellum), others don't, autotrophs or heterotrophs, reproduce asexually by binary fission.

Kingdom Protista

Mostly unicellular (some multi-cellular), eukaryote, some move (cilia, flagella, pseudopodia), others don't, autotrophs or heterotrophs.

Kingdom Fungi

Multicellular eukaryotes (except yeast), mainly do not move, heterotrophs, reproduce asexually and sexually, decomposers.

Kingdom Plantae

All multicellular eukaryotes, autotrophs (provide food for almost all heterotrophs on Earth), reproduce asexually and sexually, cell walls made of cellulose.

Kingdom Animalia

Multicellular with specialized tissues, eukaryotes (no cell wall), heterotrophs, most reproduce sexually, do move (motile).