Biological Classification (Video Notes)

Vocabulary flashcards covering key terms from the lecture notes on biological classification and the Whittaker five-kingdom system, along with details on fungi, protists, bacteria, viruses, and symbiotic associations.

Aristole

-earliest scientist to classify living organisms into groups based on shared characteristics. He laid the groundwork for future biological classification systems.

-used simple morphlogical characters tp classify plants into trees shrubs and herbs

-divided animals into two groups those which had red blood and those that did not

Drawbacks for Aristole classificstion

1. Did not distinguish between eukaryote and prokaryote, or photosynthetic and non-photosynthetic organisms.
   

2. A large number of organisms did not fall into either category.

3. Classification was based on gross morphology, not including:

- Cell structure

- Nature of wall

- Mode of nutrition

- Habitat

- Methods of reproduction

- Phylogenetic relationships

Fungi

-cell wall present with chitin

-multicellular loose tissue

-hetro{sapro\parasitic}

Kingdom Monera

Bacteria; prokaryotic, unicellular organisms; the sole members of the Monera kingdom.

Archaebacteria

Bacteria living in extreme habitats; different cell wall structure; includes methanogens, halophiles and thermoacidophiles.

Kingdom Protista

All single-celled eukaryotes; a bridge between plants, animals and fungi; includes Chrysophytes, Dinoflagellates, Euglenoids, Slime Moulds and Protozoans.

Kingdom Fungi

Heterotrophic eukaryotes with cell walls of chitin; mostly multicellular (yeasts are unicellular); saprophytes or parasites; reproduce by spores; have hyphae forming a mycelium.

Kingdom Plantae

Eukaryotic, chlorophyll-containing organisms with cellulose cell walls; includes algae, bryophytes, pteridophytes, gymnosperms and angiosperms; life cycle shows alternation of generations.

Kingdom Animalia

Heterotrophic, multicellular eukaryotes lacking cell walls; holozoic nutrition; show growth, movement, and embryological development.

Eubacteria

True bacteria; rigid cell walls; some are motile with flagella; includes cyanobacteria; reproduce by fission; Mycoplasma lack cell walls.

Cyanobacteria

Photosynthetic autotrophs with chlorophyll a; can be unicellular, colonial or filamentous; may form blooms; often have a gelatinous sheath.

Nostoc (cyanobacteria)

Cyanobacterium capable of nitrogen fixation in heterocysts; forms colonies in a gelatinous sheath.

Anabaena (cyanobacteria)

Cyanobacterium that fixes atmospheric nitrogen in specialized cells called heterocysts.

Mycoplasma

Bacteria lacking a cell wall; among the smallest living cells; can survive without oxygen; many are pathogenic.

Chlamydomonas

Unicellular green alga in Protista; photosynthetic; typically has two flagella.

Chlorella

Unicellular green alga in Protista; photosynthetic.

Paramoecium

Ciliate protozoan; freshwater; moves with numerous cilia and has a gullet for feeding.

Amoeba

Amoeboid protozoan; moves and feeds with pseudopodia; some species are parasites.

Dinoflagellates

Mostly marine, photosynthetic protists with two flagella and cellulose plates; can cause red tides and produce toxins.

Chrysophytes

Group including diatoms and golden algae; mostly aquatic; silica cell walls; important producers.

Diatoms

Chrysophytes with silica-based cell walls; contribute to diatomaceous earth used in polishing and filtration.

Euglenoids

Freshwater protists with a pellicle and two flagella; photosynthetic in light, heterotrophic in darkness; example: Euglena.

Slime Moulds

Saprophytic protists; form plasmodium; can differentiate into fruiting bodies bearing resistant spores.

Protozoans

Heterotrophic single-celled eukaryotes; four major groups: Amoeboid, Flagellated, Ciliated, Sporozoans.

Amoeboid protozoans

Move using pseudopodia; prey capture by false feet; some have silica shells in marine forms; includes Amoeba.

Flagellated protozoans

Protozoans with one or more flagella; free-living or parasitic.

Ciliated protozoans

Aquatic protozoans with many cilia; use a gullet for feeding; example: Paramoecium.

Sporozoans

Protozoans with infectious spore-like stage; includes Plasmodium (malaria parasite).

Phycomycetes

Fungi with aquatic habitats; aseptate (coenocytic) mycelium; sporangia producing zoospores or aplanospores; zygospore formation.

Ascomycetes

Sac fungi; septate mycelium; sexual spores (ascospores) produced in asci within ascocarps; includes Aspergillus, Neurospora; includes yeasts like Saccharomyces.

Basidiomycetes

Club fungi; basidia bearing basidiospores; includes mushrooms, rusts, smuts; septate hyphae; plasmogamy followed by basidium formation.

Deuteromycetes

Imperfect fungi; only asexual spores known (conidia) for a long time; later linked to other phyla when sexual stages discovered.

Lichens

Symbiotic association between algae (phycobiont) and fungi (mycobiont); mutualistic; algae provides food, fungi provide shelter and mineral uptake.

Mycorrhiza

Symbiotic association between fungi and plant roots; mutualistic nutrient exchange enhances water and mineral uptake.

Alternation of generations

Plant life cycle with two generations: a diploid sporophyte and a haploid gametophyte that alternate.

Viruses

Acellular, obligate parasites with nucleoprotein; contain RNA or DNA (not both); require a host cell to replicate; often crystalline outside hosts.

Viroids

Small infectious RNAs lacking a protein coat; cause plant diseases (e.g., potato spindle tuber).

Prions

Infectious proteins causing neurodegenerative diseases (e.g., BSE/mad cow disease, CJD in humans).

Conidia

Asexual spores produced externally on conidiophores in fungi.

Sporangiospores

Asexual spores produced inside sporangia in fungi.

Ascospores

Sexual spores produced in asci within ascocarps (ascomycetes).

Basidiospores

Sexual spores produced on basidia in basidiomycetes.

Plasmogamy

Fusion of cytoplasm between two mating types in fungi, often leading to a dikaryotic cell.

Karyogamy

Fusion of nuclei during fungal sexual reproduction, followed by meiosis to form haploid spores.

Dikaryon

Cell stage in fungi with two genetically distinct nuclei per cell prior to karyogamy.

Dikaryophase

Phase in some fungi where two nuclei share a single cell before nuclei fuse.

Hyphae

Thread-like filaments forming the fungal body; may be septate or coenocytic.

Mycelium

Network of hyphae that constitutes the body of a fungus.

Septate

Hyphae divided by septa (cross walls).

Coenocytic

Hyphae without septa; multinucleate.

Monera

-prokaryote

-noncellulosic (polysacchiride +amino acids) cellwall

- auto and hetro

Protista

-eukaryote

-cell wall present in some

-auto and hetro

Criteria used for classification

1. Cell structure
   

2. Body organization

3. Mode of nutrition

4. Reproduction

5. Phylogenetic relationships

Six kingdom classfication

1. Proposed by Carl Woese.
   

2. Based on ribosome type (70s/80s).

3. Led to the 3-domain system: Archaea, Eubacteria, and Eukarya.

Reasons which influenced 5 kingdoms

1. Initially, bacteria, BGA (blue-green algae), fungi, mosses, ferns, gymnosperms, and angiosperms were grouped under Plantae, based on the common