TOPIC 6 CLASSIFICATION & CLADOGRAMS

Systematics

is the scientific study of the diversity of organisms and their relationships. It includes the classification, naming, and determining the evolutionary relationships among species.

Taxonomy (Linnaeus, 1750s)

is a branch of systematics that focuses on the classification and naming of organisms based on shared characteristics and evolutionary history

Phylogeny

is the evolutionary history and relationship of organisms, often depicted in a tree-like diagram that shows how different species are related through common ancestors.

Order of Classifications (Inclusive → Exclusive)

Domain→Kingdom→Phylon→Class→Order→Family→Genus→Species (DO KEEP POTS CLEAN OR FAMILY GETS SICK)

Species Name

Genus specific epithet

Specific epithet

Which member of the genus

Cladogram

branching diagrams showing ancestry and derived characteristics

Phylogenetic Tree

includes length of time of extinction (more specific then the cladogram)

Sister Taxa

They are the same age because they share the same ancestor with no other species

What type of clade is this?

Monophyletic

What type of clade is this?

Polyphyletic

What type of clade is this?

Paraphyletic

3 Domain System

Bacteria, Archea, Eukarya

6 Kingdom System

Bacteria, Archae, Protista, Plantae, Fungi, Animalia

What domain are humans most closely related to?

Archea

What domain are humans?

Eukarya

How old is the Earth?

4.5 billion years old

Bacteria & Archaea Characteristics

• Microbes (1-10 micrometers)

• Smaller than eukaryote cells

• unicellular & prokaryotic

• Ring of DNA - 0.001 times as much as eukaryotes

• More abundant than eukaryotes

• Important in medicine, industry and environment

• Bacteria IS pathogenic archaea is NOT

What is Bioremediation?

Eco-friendly process that uses living organisms, to detoxify or remove environmental pollutants from soil, water and air

Ecology Importance of Prokaryotes

• Decomposition, bioremediation

• Industrial waste sites

• Nitrogen fixation

• Mutualistic relationships (lichens, intestines)

• Commercial use

What is an intron?

Introns is a non-coding nucleotide sequence within a gene that is copied into RNA during transcription but it removed before the RNA is translated into a protein

Eubacteria

• Common Name: Bacteria

• No introns

• Diverse nutrition and respiration

Prokaryotic Reproduction

• 1-3 hours

• Binary Fission

• Conjugation

What is Binary Fission?

Form of asexual reproduction and cellular division used by prokaryotic organism (like bacteria or archaea) to split into two genetically identical daughter cells

What is Conjugation?

The direct transfer of genetic material between two cells that are temporality joined together

Shapes of Eubacteria

1. Cocci

2. Bacilli

3. Sprilli

They only move forward and reverse

Peptidoglycan

Peptides and sugars in cell walls

Bacteria Stains

• Pos. = purple

• Neg. = pink/orange

Cyanobacteria

• was ‘blue-green algae”

• dominate aquatic environments

• plant-like & photosynthetic

• formed ozone layer, brought life to land

• 20-30% of worlds oxygen

• some in lichen

Bacteria

• can from endospores when exposed to harsh environments (go formant)

• survive boiling water

• only die at 248 F

• Adapt quickly to their environment through natural selection

• Have proteins with strongest bonds that do not denature in high heat, salt or acidity

Archaea

• cell wall does not contain peptidoglycan

• cell membrane has lipids not found in other organisms

• gene are interrupted buy introns (like eukaryotes unlike eubacteria)

• very abundant in plankton

• many habitats (soil, marshes, oceans)

• many are extremophiles

What is an extremophile?

Organism that has evolved to grow and thrive in environments once considered too harsh or hostile to support life

Methanogen

Produce methane poisoned by o2 (sewage treatment)

Thermophiles

Live in extreme temperatures

Halophiles

Live in high saline

Protists

• “junk draw”

• unicellular, complex (10x larger than most bacteria)

• most aquatic

• form colonies

• colonial photosynthetic protists = algae (1/2 worlds oxygen)

• reproduce both sexually and asexually

• animal like, plant like and fungus like

How do protist feed?

Ingestive AND absorptive

How to protists move?

• crawling with pseudopodia

• swimming via flagella

• swimming via cilla

Protist - ecological importance?

• food chain

• playtoplakton produce O2

• decomposition

• symbiotic relationships (mutual and parasitic)

• medicine

Fungi (eukarya)

• more on land

• multicellular (exception of yeast)

• heterotrophic

• decomposers

• closely related to animals

• cell walls contain chitlin

• main body is hyphae

• sexual and asexual reproduction

• diverse ~70,000 species known

Fungi - Nutrition

• severe digestive enzymes (exoenzymes) into surroundings

• absorb the organic molecules

• great surface area to volume ratio

• break down cellulose

• decompose wood

• some fungi are carnivores

• external extracellular digestion

• 30% of fungi are parasites

  • mycorrhizae (80% of all plants)

    • live in roots

    • help feed them

• lichens: green algae live in fungal hyphae

What are humans?

Internal extracellular

What is a hyphae?

A long, branching, thread-like tubular structure that makes up the main vegetative body of a fungus

All algae are…

Protist BUT blue/green

Nonvascular Plants

• Bryophytes

  • mosses, close to water

Vascular Plants

• Tissues allow height

  • seedless = pteridophytes (fern)

  • seedbearing = pollen

    • Gymnosperm - evergreen

    • Angiosperms - flowering plant (more successful)

Monoclat (Angiosperms)

• foral in three parts

• parellel leaf veins

• one cotyldia

• crops

Dicots (Angiosperms)

• foral parts in fours

• netlife leaf veins

• most common trees

What is Alternation of Generations?

• sporophyte produces haploid by meiosis

• gametophyte produces haploid gametes (no meiosis)

Animals (Animalia)

• from single celled protist ancestor

• multicellular, heterotopic, feed by ingestion

• lack cell wall

• muscles for movement

• have regulatory HOX gene

• nervous tissue

• respiratory/gas exchange & transport nutrients

• skeleton support

Animals Body Plan - Tissue Type

• only sponges lack germ layer of tissue in embryo

• all others have germ layers

Diploblasts - Tissue Types

• 2: Cnidaria

  • Ectoderm

  • Endoderm

Triploblasts - Tissue Types

• 3: All other animals

  • ecotderm

  • mesoderm

  • endoderm

Embryotic Development - Protostomes

• mouth develops first

• arthropod

• molluses

• annelids

Embryotic Development - Deuterostomes

• mouth develops second

• chordates

• echinoderms

Symmetry

• Asymmetry

• Bilateral

• Radical

What is cephalization?

Having a definite head region, visually with felling and sensory features

What is a Echinoderm?

• pentaradial symmetry (adults)

• internal skeleton

• gills

• spiny skin

• water vascular system for movement via tube feet

  • ex. sea stars, brittle stars, sea urchins, sea cucumbers, sea lilies

What is a mollusk?

Foot, soft body, mantle (thick tissue that protects body-and may secrete a shell)

What are the three major mollusks classes?

• Gastropod (snails) *only terrestrial mollusk

• Bivalve (clams)

• Cephalopod (octopi)

Characteristic of Chordates

• notochord

• dorsal, hollow nerve cord

• pharyngeal slits or clefts

• muscular, post-anal tail

Notochord

longitudinal, flexible rod located between the digestive and the nerve cord

Dorsal, hollow nerve cord

eventually develops into the brain and spinal cord

Pharyngeal slits

become modified for gas exchange, jaw support, and/or hearing

Agnatha (Fish)

Lampreys and hagfish-jawless, most are parasitic

Chondrickthyes (fish)

Cartilage skeleton, sharks, rays, skates

Osteichtyhes (fish)

Bony skeleton swim bladder to adjust depth in water

• rayfinned: fins supported by bony structures called rays

Osteichthyes (fish)

Bony skeleton, swim bladder to adjust depth in water

• lobe-finned: fins long fleshy and muscular = can “walk” on seabed; ancestors of amphilbians

Platyhelminthes (flatworm)

bilateral symmetry, incomplete digestive system, acoelomate

• some are free-living (planarians)

• most are parasitifc (tapeworms, flukes)

Nematodes (roundworms)

• Complete digestive system, bilateral many are parasistiv (ex. trichinella, causes trichinosis; heartworms in dogs), but most are free-living (often small/microscopic) in soil and water

Annelids

• Segmented (for burrowing), coelomate, closed circulatory system

• earthworm, leech, Lumbriculus

• tube worms, bristle worms

Invertebrates are what percent of animals?

97%

Amphibia

• evolved from lobe-finned fished… most return to water to reproduce (external fertilization) - external respiration, skin must stay moist (also have lungs for respiration)

What are the three order of amphibians?

• Anura (frogs/toads)

• Apoda (caecillians)

• Caudate (salamanders)

Class Sauropsida (reptiles and birds)

Shelled amniotic egg, makes reproduction on land possible… also have internal fertilization and dry scaly skin

What are Aves?

Endothermic (all previous groups have been ectothermic), feather, air sacs, hollow bones, amniotic egg

• archaeopteryz: oldest known bird, feathered wings but more like small bidpedal dinosaur

What are Arthropods?

External exoskeleton with chitin, segmented body (specialized), joined appendages—most successful group of animals

Subphyla (Arthropods)

Spider, ticks pincers or fangs

Crustacea: crabs—2 pairs of antennae

Hexapoda (Arthropods)

Insects—3 body parts

• milli/centipedes: many segments

Characteristics of Mamalia?

• hair/fur

• mammary glands

• increased brain capacity

• specialized teeth

Monotremes (Animalia)

• egg-laying (but still nurse young

• spiny anteater (echidna) and duck-billed platypys, both in Austraulua

• prototheria

• duck-billed playpus

Marsupials

• young born early, finish development in mother’s pouch—most in Australia (except opossum)

• metatheria

• tasmanian devil

• kangaroo

Eutherian/placental mammals

Most mammals; placenta nourishes young within mother-safer, more efficient

• eutheria