Lab 10: Prokaryotic Cells (Cusic Topic 2)

This set of flashcards covers key concepts from Lab 10 on prokaryotic cells, including taxonomy, characteristics of prokaryotes, mechanisms of bacterial reproduction and genetic variation, and relationships in symbiosis.

What are the three characteristics that distinguish prokaryotic cells from eukaryotic cells?

Prokaryotic cells have circular DNA, no membrane-bound nucleus, and no membrane-bound organelles.

Which domains are prokaryotes currently classified into?

Prokaryotes are classified into two domains: Archaea and Bacteria.

What are the three main types of Archaea based on their habitat?

Methanogens, Halophiles, and Thermoacidophiles.

How do bacteria achieve genetic variation if they reproduce asexually through binary fission?

Bacteria achieve genetic variation through mechanisms like conjugation, transformation, and transduction.

What is the role of bacteriophages in bacterial genetics?

Bacteriophages transfer DNA between prokaryotes by injecting DNA into bacteria.

What are the main nutrition types of bacteria?

Photoautotrophs, Chemoautotrophs, Photoheterotrophs, and Chemoheterotrophs.

What is the significance of the zone of inhibition in antibiotic susceptibility testing?

The zone of inhibition indicates the effectiveness of an antibiotic against a bacterial species; larger zones signify more effective antibiotics.

What are the differences in the cell wall structure of Gram-positive and Gram-negative bacteria?

Gram-positive bacteria have a thick peptidoglycan layer that stains violet, while Gram-negative bacteria have a thin layer and an outer membrane that stains red/pink.

Define mutualism, commensalism, and parasitism.

Mutualism: both species benefit; Commensalism: one benefits and the other is neither helped nor harmed; Parasitism: one benefits at the expense of the other.

What is the function of plasmids in bacteria?

Plasmids are self-replicating circular DNA that assist in horizontal gene transfer and can carry genes for antibiotic resistance.

What are the three major domains of life?

The three major domains of life are Bacteria, Archaea, and Eukarya.

What is the main difference between Archaea and Bacteria?

Archaea and Bacteria differ mostly in their cell wall composition, genetic sequences, and metabolic pathways.

What types of environments do Archaea typically inhabit?

Archaea are known to inhabit extreme environments such as hot springs, salt lakes, and the deep sea, as well as more common environments.

How do Bacteria reproduce?

Bacteria primarily reproduce asexually through a process called binary fission.

What role do Bacteria play in ecosystems?

Bacteria play essential roles in ecosystems as decomposers, nitrogen fixers, and contributors to nutrient cycling.

What are extremophiles?

Extremophiles are organisms, including many Archaea, that thrive in extreme conditions such as high temperature, salinity, or pH levels.

Do Archaea have peptidoglycan in their cell walls?

No, Archaea do not have peptidoglycan in their cell walls, unlike many bacteria.