Zoology Lecture 13: Microbial Life - Prokaryotes and Protists

This set of vocabulary flashcards covers the fundamental concepts of Zoology Lecture 13, including the classification of life, characteristics and reproduction of prokaryotes, and the diversity of protists.

Zoology

The scientific study of animals, including their structure, embryology, classification, habits, distribution, and ecosystem interactions.

MRS GREN

An acronym for the 7 biological processes: Movement, Reproduction, Sensitivity, Growth, Respiration, Excretion, and Nutrition.

Domain

The highest taxonomic rank of organisms; the three domains mentioned are Bacteria, Archaea, and Eukarya.

Vertebrates

Animals that possess a backbone.

Invertebrates

Animals that do not possess a backbone.

Prokaryote

Meaning 'before a nucleus,' these are single-celled organisms in the domains Bacteria and Archaea that lack a membrane-enclosed nucleus and organelles.

Eukaryote

Any cell or organism that contains a clearly defined nucleus and membrane-bound organelles, including animals, plants, fungi, and protists.

Coccus

A sphere-shaped prokaryote; plural is cocci.

Bacillus

A rod-shaped prokaryote; plural is bacilli.

Spirochete

A long and flexible spiral-shaped prokaryote.

Spirillum

A short and rigid spiral-shaped prokaryote.

Streptococcus

A chain-like arrangement of sphere-shaped bacteria.

Staphylococci

A cluster-like arrangement of sphere-shaped bacteria.

Gram-positive bacteria

Bacteria that have a cell wall containing a large amount of peptidoglycan.

Gram-negative bacteria

Bacteria with very little peptidoglycan located between the plasma membrane and an outer membrane.

Peptidoglycan

A polymer that makes up the cell wall of most bacteria, preventing cells from bursting or collapsing during osmotic changes.

Capsule

A well-organized glycocalyx that helps prokaryotes adhere to surfaces or other individuals in a colony.

Fimbriae

Short, bristle-like fibers extending from the surface of a prokaryote used for adherence.

Flagella

Longer, whip-like structures that can rotate $360^\text{o}$ to cause cell movement.

Sex pilus

A structure used by prokaryotes for the transfer of DNA.

Binary fission

An asexual reproduction method where an organism duplicates its DNA and divides into two genetically identical daughter cells.

Conjugation

A form of sexual reproduction in bacteria involving the direct transfer of genetic material via a temporary conjugation bridge.

Endospore

A resistant structure produced inside a cell that encloses a copy of the chromosome in a thick protective coat to survive harsh conditions.

Photoautotrophs

Organisms that harness sunlight for energy and use $CO_2$ for carbon.

Photoheterotrophs

Organisms that obtain energy from sunlight but get their carbon from organic sources.

Chemoautotrophs

Organisms that harvest energy from inorganic chemicals and use carbon from $CO_2$ to make organic molecules.

Chemoheterotrophs

Organisms that acquire both energy and carbon from organic molecules.

Extreme thermophiles

Archaea that can survive in extreme temperatures, such as hydrothermal vents and hot springs.

Extreme halophiles

Archaea that can survive in extremely salty environments, such as the Dead Sea.

Biofilms

Surface-coating colonies of prokaryotes that allow for metabolic cooperation and adherence to surfaces via a glue-like substance.

Bioremediation

The use of organisms, such as prokaryotic biofilms, to remove pollutants from the environment.

Protist

Any eukaryotic organism that is not an animal, plant, or fungus.

Mixotrophs

Protists capable of both photosynthesis (autotrophy) and heterotrophy, depending on light and nutrient availability.

Holozoic nutrition

The ingestion and internal processing of solid and liquid food, seen in herbivores, carnivores, and omnivores.

Saprophytic nutrition

A type of nutrition involving feeding on dead and decaying organisms; characteristic of detritovores.

Parasitic nutrition

Nutrition where organisms live in or on a host and acquire food at the host's expense.

Multiple fission

A form of asexual reproduction where the nucleus divides many times before the cytoplasm divides, forming several daughter cells.

Budding

Asexual reproduction where outgrowths from the parent form and pinch off to live independently or form a colony.

Isogamy

Sexual reproduction involving the fusion of isogametes, which are gametes that are morphologically the same.

Anisogametes

Gametes that are morphologically different, such as the small male microgamete (sperm) and the large female macrogamete (egg).

Syngamy

The complete fusion of two cells or gametes, resulting in the formation of a zygote or oospore.

Autogamy

The fusion of haploid nuclei derived from the same individual.

Hologamy

The fusion of two mature protists.