Viruses, Archaea, Bacteria, and Kingdom Protista Lecture Notes

A complete set of vocabulary flashcards covering the characteristics, classifications, and reproduction of viruses, bacteria, archaea, and various protist lineages based on the lecture transcript.

Viruses

Non-cellular infectious agents consisting of a protein coat around a core of DNA or RNA that replicate only in a host cell and evolve by natural selection.

Retrovirus

An RNA virus that uses reverse transcriptase to produce viral DNA in a host cell.

Viral recombination

The process where viral genomes exchange genes when two viruses infect a host at the same time.

Prokaryotes

Unicellular organisms, including Bacteria and Archaea, characterized by small cell size ($1-5\,\mu\text{m}$) and the absence of a nucleus, endoplasmic reticulum, or Golgi bodies.

Binary fission

A form of asexual reproduction in prokaryotes where the circular chromosome is duplicated and the cell divides into two genetically identical cells.

Transformation

The process of horizontal gene transfer involving the introduction of foreign DNA into a cell, as seen in $Streptococcus\ pneumonia$.

Transduction

The process by which DNA is transferred from one bacterium to another by a virus.

Peptidoglycan

A polymer of sugars cross-linked by short polypeptides that forms the cell wall in bacteria.

Cocci

Spherical-shaped bacterial cells used for identification and classification.

Bacilli

Rod-shaped bacterial cells.

Spirochete

Spiral-shaped bacterial cells.

Cyanobacteria

Photosynthetic prokaryotes that fix atmospheric nitrogen into ammonia and are the ancestors of chloroplasts in eukaryotes.

Normal flora

Normally harmless or beneficial microorganisms that live in or on a body, such as $E.\ coli$ (which produces vit. K) and $Lactobacillus\ sp.$ (which produces vit. B).

Extreme Halophiles

A type of Archaea that thrives in environments with extremely high salt concentrations.

Extreme Thermophiles

A type of Archaea that thrives in environments with extremely high temperatures.

Mixotrophy

A mode of nutrition in Protists, such as Euglena, that combines autotrophy and heterotrophy.

Flagellates

Protozoans like $Trypanosomal$, a blood parasite with a single large mitochondrion that causes sleeping sickness via the tsetse fly.

Ciliates

Protists like Paramecium that use cilia to move and sweep food into a mouth-like gullet and utilize contractile vacuoles.

Pseudopodia

Lobe-shaped extensions used by Amoebas for movement and feeding.

Forams

Protists characterized by a calcium carbonate shell.

Choanoflagellates

The closest known protistan relatives of animals, featuring a flagellum surrounded by a collar of threadlike projections similar to sponge cells.

Plasmodial Slime Molds

Social amoebas that form a plasmodium, described as one big mass of cytoplasm with many nuclei.

Cellular Slime Molds

Social amoebas that aggregate into a mobile, multicelled "slug" to seek suitable spots for forming a fruiting body when food is scarce.

Dinoflagellates

Unicellular algae with two flagella in perpendicular grooves that cause them to spin; some species cause "red tides" during summer blooms.

Diatoms

Unicellular algae with a two-part shell made of silica that store food in the form of lipids.

Green Algae

Protists closely related to land plants that contain chlorophyll for photosynthesis and cellulose in their cell walls.

Fucoxanthin

The brown pigment found in multicellular algae such as Kelp.

Algins

Substances sourced from multicellular algae used as thickeners and emulsifiers.