BIOLOGICAL CLASSIFICATION

Flashcards covering key concepts from the Biological Classification chapter, including classification systems, the five kingdoms, and related topics like viruses and lichens.

How did Aristotle initially classify living organisms?

Classified plants into trees, shrubs, and herbs based on simple morphological characters and divided animals into those with and without red blood.

What were the limitations of the Two Kingdom system of classification?

Did not distinguish between eukaryotes and prokaryotes, unicellular and multicellular organisms, and photosynthetic and non-photosynthetic organisms.

What were the main criteria for classification used by R.H. Whittaker in his Five Kingdom Classification?

Cell structure, body organisation, mode of nutrition, reproduction, and phylogenetic relationships.

What are the five kingdoms in Whittaker's classification?

Monera, Protista, Fungi, Plantae, and Animalia.

Where do archaebacteria typically live?

Extreme salty areas (halophiles), hot springs (thermoacidophiles), and marshy areas (methanogens).

What characterizes eubacteria or 'true bacteria'?

The presence of a rigid cell wall and, if motile, a flagellum.

Which groups are included under Kingdom Protista?

Chrysophytes, Dinoflagellates, Euglenoids, Slime moulds, and Protozoans.

What is unique about the cell walls of diatoms?

Diatoms have cell walls embedded with silica, forming indestructible shells.

What do euglenoids have instead of a cell wall?

A protein-rich layer called pellicle that makes their body flexible.

What are the four major groups of protozoans?

Amoeboid, Flagellated, Ciliated, and Sporozoans.

What are the long, slender thread-like structures that make up fungi called?

Hyphae, and the network of hyphae is known as mycelium.

By what vegetative means can fungi reproduce?

Fragmentation, fission, and budding.

Where are members of phycomycetes typically found?

Aquatic habitats, decaying wood in moist places, or as obligate parasites on plants.

How do ascomycetes reproduce asexually and sexually?

Asexual spores are conidia produced exogenously, and sexual spores are ascospores produced endogenously in asci.

What are some common forms of basidiomycetes?

Mushrooms, bracket fungi, or puffballs.

Why are deuteromycetes known as imperfect fungi?

Only the asexual or vegetative phases are known in deuteromycetes.

Which groups are included in the plantae kingdom?

Algae, bryophytes, pteridophytes, gymnosperms and angiosperms.

Why were viruses did not find a place in the five kingdom classification?

Viruses are non-cellular and have an inert crystalline structure outside the living cell.

What type of genetic material do viruses that infect plants typically have?

Single-stranded RNA.

What characterizes a viroid?

A free RNA molecule without a protein coat.

What are lichens?

Symbiotic associations between algae (phycobiont) and fungi (mycobiont).