MICRO 20 CH. 4 (EXAM 2)
Pili
Attachment to other bacterial cells
Metachromatic granules are concentrated ______ found in _____
PO4, Corynebacterium
True or false: Mycoplasmas are pleomorphic because they do not contain a cell wall for shape.
True
Which of the following is not found in all bacterial cells
actin cytoskeleton
Major factor that stimulates endospore formation
depletion of nutrients
Only Gram-___ bacteria possess an outer membrane
negative
Which of the following is present in both gram-positive and gram-negative cell walls?
peptidoglycan
Part of the cell wall of mycobacteria
peptidoglycan and mycelia acid
During ___, bacterial cells move by flagellar motion in response to light
phototaxis
Small proteinaceous appendages in gram-negative bacteria that function in DNA exchange are called conjugation
pili
The tendency of cells of the same species to have a variety of shapes and sizes is called
pleomorphism
In any ___ arrangement, flagella are attached at either one end of both ends of a bacterium (e.g. lophotrikhous or amphitrichous)
polar
The Gram ____ cell wall contains peptidoglycan, teichoic acid, and lipoteichoic acid
positive
The two main functions of the glycocalyx are ____ and ____
protection; adherence
Functions of the bacterial cell membrane
provide a site for energy reactions, barrier between the internal and external contents of the cell, provide a site for nutrient processing and synthesis
Proteins are synthesized on the _______, a small spherical structure located in the cytoplasm or attached to the rough endoplasmic reticulum. (RER)
ribosome
The site of protein synthesis in the cell, known as the ___, is composed of rRNA and protein
ribosome
NOT external components of a prokaryotic cell
ribosomes, inclusions
A tightly-coiled yet flexible helical bacterium is described as a(n)
spirochete
Corkscrew-shaped bacteria are called:
spirochetes
____ are spiral-shaped bacteria characterized by periplasmic flagella and display a worm-like mode of locomotion
spirochetes
The depletion of nutrients is a stimulus for ___ in bacteria
sporulation
The prefix "____-" means "in grape like clusters"
staphylo
Which of the following is a primary bacterial cell wall function
support
Bacterial endospores function in
survival
Pili are typically used for
conjugation
The genetic exchange of material through pili is termed ____.
conjugation
Elongates, rigid tubes on gram-negative bacteria that are involved in the transfer of DNA from one cell to another are called:
conjugation pili
The cell membrane consists of a ___ bilayer with embedded ____
lipid; proteins
LPS is an abbreviation for
lipopolysaccharide
The outer membrane of a Gram-Negative cell contains:
lipoproteins, lipopolysaccharides
The ___ bacteria naturally have no cell wall, but have a cytoplasmic membrane that is stabilized by sterols
mycoplasma
Which of the following prokaryotes lacks cell walls
mycoplasmas
Endospore formation (from stimulus to mature endospore)
1. DNA replication 2. Separation of cell 3. Sporangiums engulfs forespore 4. Synthesis of spore layers 5. Deposition of cortex and outer coat layers 6. Mature endospore formed
order of spore germination
1. Initiation by a specific germination agent 2. Enzymes digest the cortex and expose the core to water 3. The core rehydrates 4. The core takes up nutrients 5. The cell becomes an active vegetative cell
The size of the ribosome in a prokaryote is
70S
What is the difference between a true nucleus and a nucleoid?
A nucleus is surrounded by a membrane and a nucleoid is not
Which is true regarding all bacterial cells?
All lack a nucleus
Which are types of flagellar arrangements with more than one flagellum
Amphitrichous, Lophotrichous, Peritrichous
A chromosome is made of:
DNA
To which taxonomic group do cyanobacteria belong
Domain Bacteria
Which phylum contains bacteria with a gram-positive cell wall
Firmicutes
Which stain is used to distinguish differences between the cell walls of medically important bacteria?
Gram stain
what is true of the condition endocarditis
It is an infection of the heart valves and lining
Which organelle is responsible for the synthesis of proteins
Ribosomes
Endospore
The inert, restive stage that is capable of resistance to harsh environmental conditions
Vegetative Cell
The metabolically active and growing stage
An example of a glycocalyx is ____
a capsule
Bacteria which use oxygen in their metabolism are known as:
aerobes
The first living cells on earth would most likely resemble which of these?
an archaeon
Plasmids carry ___ genes
antibiotic resistance, nonessential
Fimbriae
attachment to surfaces
A(n) ___ filament is a periplasmic flagellum found in some spirochete bacteria
axial
The proper term for a rod-shaped bacterial cell is a(n) ____
bacillus
Rob-shaped bacterial cells are called ___, whereas gently curved rod-shaped cells are referred to as a ____
bacillus; vibrio
Peptidoglycan's are components of the cell walls in ____
bacteria
A(n) ___ forms from a complex association of microorganisms that grow on a surface or tissue matrix
biofilm
Why is it difficult to group bacteria into species
can accept genetic materials from others; do not use a typical mode of sexual production; can alter their genetic makeup
The ___ is the name given to a structure external to and bound tightly to the cell wall that is made of polysaccharides and proteins and contributes to the pathogenicity of the organism
capsule
Viruses are not considered living things because they only show signs of life when they are inside a host ___
cell
Which of the following is considered to be the basic unit of life?
cell
All cells contain which of the following characteristics
cell membrane, ribosomes, chromosomes
Which structure is not a component of all cells?
cell wall
The two main components of the cell envelope in most bacteria are the:
cell wall and cell membrane
The function of teichoic acid and lipoteichoic acid in the Gram-positive cell wall includes
cell wall enlargement, and cell wall maintenance
"Strepto-" indicates cells are arranged in:
chains
The movement of an organism towards or away from a chemical stimulus is called ____.
chemotaxis
What are the three most common shapes of bacterial cells?
coccus, spirillum, bacillus
The cell membrane surrounds a complex solution of organic materials and salts that is referred to as ____.
cytoplasm
Recent evidence suggests that bacteria, like eukaryotic cells, maintain and support cell shape through a network of protein fibers called the ___
cytoskeleton
The prefix "___-" means "in pairs"
diplo
Which of the following are examples of organelles
endoplasmic reticulum, golgi apparatus, vacuoles
In bacteria, sporulation is the process of ____ formation
endospore
The LPS layer in gram-negative cell walls releases _____ that cause ______
endotoxins, fever
NOT internal components of a prokaryotic cell
fimbriae, glycocalyx, pili
Appendages that propel bacterial cells through an aqueous environment include _____ and axial filaments.
flagella
The major locomotor structures in bacteria are ____
flagella
Where did the MRSA pathogen likely originate
from the patients earlier skin infection
The ___ is a polysaccharide protective coating outside of the bacterial cell wall that is called either a capsule or slime layer based on its structure
glycocalyx
The ___ refers to a coating of macromolecules around bacteria cells that protect them and help them adhere to their environment
glycocalyx
Pili are appendages in ____ bacteria that serve as means of ____
gram-negative, genetic exchange
Which are inherent to life
heredity; growth and development; metabolism
With respect to their source of nutrition, most bacteria are ____
heterotrophic
Bacteria often store excess nutrients in membrane bound compartments called ____
inclusions
Cytoplasmic _____, such as granules or vesicles, can store organic and inorganic nutrients and even gases or magnetic iron oxides
inclusions
Two important diseases caused by mycobacteria are:
leprosy and tuberculosis
A cell having a single, polar flagellar is SPECIFICALLY described as having a ___ flagellar arrangement
monotrichous
The ability to move is referred to as ____
motility
Flagella
motility (long appendages)
Cilia
motility (short appendages)
A(n) ____ _____ parasite requires a host cell in order to survive
obligate intracellular
The _____ _____ of the gram-negative cell envelope provides protection against some antimicrobial chemicals
outer membrane
Anaerobic bacteria do not use ___ in their metabolism
oxygen
An arrangement in packets of eight cells is described as a ______
sarcina
Methods used to identify bacteria
serological analysis, cell morphology, bacterial biochemistry, genetic techniques
A coccus is a _____ - shaped bacterial cell
spherical
A cubical arrangement of four cocci is referred to as a ____
tetrad
The major difference between a spirochete and a spirillum is
the nature of motility
Viruses are not considered living things because
they are not cells; they lack metabolism; and they cannot reproduce by themselves
A curved rod (comma-shaped bacterium) is specifically described as a(n)
vibrio
