Bacterial Structure (Prokaryotes, tutorial #4)) Flashcards
pili
Hair-like structures that help bacteria attach to surfaces and other bacteria.
plasmids
genetic material (DNA)
ribosomes
structures that make proteins
cytoplasm
a gel-like material in which the ribosomes and genetic material are suspended
cytoplasmic membrane
a thin layer of phospholipids and proteins that controls the movement of nutrients in and out of the cell
cell wall
a rigid wall that gives the cell its structure and protects the plasma membrane
Xapsule
a third layer that helps prevent the bacteria from dying out or being engulfed by larger microorganisms (only present in some types of bacteria)
Nucleiod
a mass of genetic material (DNA)
Flagellum
structure that helps the bacteria move around and sense their environment.
spherical bacterial cell shape classification
coccus/ cocci
rod bacterial cell shape classification
bacillus/bacilli
spiral bacterial cell shape classification
spirillum/ spirilli
what are the three factors that enable prokaryotes (specifically bacteria) to grow and reproduce quickly?
small genome, simple structure, and binary fission
Which has more peptidoglycan in their cell walls: gram-positive bacteria or gram-negative bacteria?
Gram-positive bacteria contain significantly more peptidoglycan in their cell walls and therefore have cell walls that are LESS structurally complex than Gram-negative bacterial cell walls; conversely, gram-negative bacterial cell walls have less peptidoglycan in their cell walls and are thereby more structurally complex. This additional complexity in their cell walls makes gram-negative bacteria more prone to antibiotic resistance and therefore also makes gram-negative bacterial infections more dangerous.
What color will gram-positive bacteria
Gram-positive bacteria will stain purple because of higher peptidoglycan content within the cell wall; conversely, gram-negative bacteria will stain pink because of lower peptidoglycan contents.
Which types of bacteria contain lipopolysaccharides?
Gram-negative bacteria; located in an extra outer membrane of the bacterial cell.
What are the three types of horizontal gene transfer used by bacteria?
Transformation, Transduction, and Conjugation.
Define Transformation
A type of horizontal gene transfer in which a prokaryote absorbs DNA from its surrounding environment- typically left behind by other bacteria when they died.
Define Conjugation
When two prokaryotic cells physically join with one another. Typically, this involves a “male” prokaryotic cell containing a plasmid termed the fertility (f) factor (F+), combining with a “female” cell which does not contain the f factor (F-). This causes the female cell to then obtain the f factor and become male.
Define Transduction
refers to the exchange of DNA between prokaryotic cells made possible by phages. phages reproduce by injecting their genetic material into bacterial cells where it is eventually
