Classification of Species and Living Things

Comprehensive vocabulary flashcards covering the classification of species, characteristics of living things (MRS GREN), classification keys, Linnaean taxonomy, five kingdoms of life, invertebrate phyla, vertebrate classes, plant classification, and indigenous environmental classification.

Classification

The grouping of organisms based on similar features among the millions of different species found on Earth.

Reasons to Classify Species

It helps scientists better understand the world, provides a basis for studying newly discovered life forms, displays the evolutionary history of life on Earth, and enables scientists to communicate across different languages and locations.

MRS GREN

A mnemonic representing the seven characteristics of all living things: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, and Nutrition.

Movement

A characteristic of living things describing their ability to move by themselves.

Respiration

The process by which living things convert energy from food into energy that can be utilized by cells.

Sensitivity

The ability of living things to detect changes in their surroundings and respond to those changes.

Growth

A characteristic of living things describing how they grow as they get older.

Reproduction

The process through which living organisms make new life.

Excretion

The process by which living things produce and remove waste products from their bodies.

Nutrition

The requirement of living things to take in nutrients to survive.

Key

A visual tool utilized in the classification of organisms.

Dichotomous Key

A classification tool featuring branches (like a tree) that always split in two, where scientists make 'yes' or 'no' decisions at each branch.

Linnaean Taxonomy

A hierarchical classification system largely created by Carl Linnaeus that operates as an enormous dichotomous key to classify all living things, starting with large groups and dividing into smaller groups.

Linnaean Taxonomic Ranks

The hierarchical levels of classification from broadest to most specific: Kingdom, Phylum, Class, Order, Family, Genus, and Species (remembered by the mnemonic 'King Philip Crawled Over Four Boozy Snails').

Double-Name System

The naming convention where every organism is named based on its genus and species. The genus is written first with a capital letter, followed by the species name with no capital, and the entire double-name is always italicized (e.g., Felis catus).

Multicellular Organism

Any living thing composed of more than one cell.

Unicellular Organism

A living thing that consists of only a single cell.

Kingdom Animalia

A kingdom consisting of all multicellular animals that gain energy from other living things, store DNA in a nucleus, and do not have a cell wall (e.g., human, frog, pelican, spider).

Kingdom Plantae

A kingdom consisting of all multicellular plants that gain energy from sunlight, store DNA in a nucleus, and possess a cell wall (e.g., trees, vines, bushes, ferns, mosses, weeds, grasses).

Kingdom Fungi

A kingdom of mostly multicellular (and some unicellular) organisms that feed on dead material from other living things, store DNA in a nucleus, and have a cell wall (e.g., mushrooms, toadstools, yeasts, moulds, truffles).

Kingdom Monera

A kingdom of unicellular organisms that possess a cell wall but lack a nucleus (e.g., bacteria).

Kingdom Protista

A kingdom of simple organisms that are primarily microscopic and unicellular (single-celled) and store their DNA in a nucleus (e.g., plankton, amoeba, algae).

Vertebrates

Animals that possess a backbone and an internal skeleton (endoskeleton), all belonging to the phylum Chordata.

Invertebrates

Animals that lack a backbone and possess either an external skeleton (exoskeleton) or no skeleton, comprising $96\%$ of all animal species.

Phylum Chordata

The taxonomic phylum to which all vertebrates belong.

Arthropods

A group of invertebrate phyla characterized by segmented bodies, paired and jointed legs, and an exoskeleton (e.g., insect, spider, centipede, scorpion).

Poriferans

Invertebrates with a spongy body with holes, found in water attached to rocks (e.g., breadcrumb sponge, glass sponge).

Molluscs

Invertebrates that have a soft body and usually possess a protective shell (e.g., snail, octopus, oyster).

Cnidarians

Invertebrates with a soft, hollow body and tentacles that live in water (e.g., coral, sea jelly, anemone).

Nematodes, Platyhelminths, and Annelids

Invertebrate worm groups characterized by soft, long bodies that can be segmented, flat, or round (e.g., leech, tapeworm, flatworm).

Echinoderms

Marine invertebrates characterized by rough, spiny skin and arms that radiate from the center of the body (e.g., sea urchin, sea cucumber, brittle star).

Vertebrate Classes Classification Criteria

The three primary features used to divide vertebrates into five classes: their body covering, how their young are born, and whether they are endotherms or ectotherms.

Endotherms

Animals that maintain a constant body temperature.

Ectotherms

Animals whose body temperature changes with the environment.

Spores

Small, simple, unicellular reproductive structures located underneath the leaf area of certain plants.

Seeds

Large, complex, multicellular reproductive units located inside flowers or fruit.

Vascular Tissue

Tube-like structures utilized by certain plants to transport water from their roots to their leaves.

Non-Vascular Plants

Plants that lack tube-like transport structures and must reside in damp places where they can absorb water through all parts of their structure.

Monocots

Flowering plants that have a single leaf growing from the seed, parallel leaf veins, and flower petals in multiples of $3$.

Dicots

Flowering plants that grow two leaves from the seed, feature spread-out or netted leaf veins, and have $4$ or $5$ flower petals.

Anangu Environmental Classification

A land classification system established by the traditional owners of the land, the Anangu people, to assist them in locating food.

Puli

An Anangu classification term for rocky areas, gorges, and stony slopes where animals go to seek shelter.

Puti

An Anangu classification term for open woodland that produces an abundance of grass after rain for kangaroos to eat, and where honey ants construct their nests.

Pila

An Anangu classification term for spinifex plains and low areas between dunes, recognized as the optimal place to gather seeds for food.