pearson chapter 1 and 2 review Flashcards
When medical devices are left in the body, bacteria may grow on them as ________, which makes them especially resistant to treatment.
biofilms
Some microorganisms can undergo ________ in which various cell types can become specialized and arise from one parent cell type.
differentiation
Compared to Eukaryotes, Bacteria and Archaea have ________ surface-to-volume ratios, causing ________ nutrient exchange
higher/higher
An organism of the genus Staphylococcus is ________, while an organism of the genus Spirochaeta is ________.
spherical: coiled
The morphology of a cell influences its
motility and surface to volume ratio
In what/which domain(s) of life is/are microorganisms represented?
all domains of life
Cyanobacteria and purple sulfur bacteria both obtain energy from light. However, only the ________ are capable of releasing _______
cyanobacteria / oxygen
Microbes that live at high temperatures in hot springs are ________.
called extremophiles.
All microorganisms require molecular oxygen to carry on life functions.
false
The process whereby microorganisms are used to help clean up pollution created by human activities is known as
bioremediation
Most microorganisms are pathogenic.
false
A bacterial cell is interpreted as gram-positive when it forms purple insoluble crystal violet-iodine complexes within the cell during the Gram stain.
true
Electron microscopes have less resolving power (resolution) than light microscopes.
false
Which of the following is NOT an accomplishment of Louis Pasteur?
developed heat sterilization techniques that involved the creation of a specialized swan-necked flask
determined that the alcohol-making process was mediated by microbial fermentation and thus refuted the theory of spontaneous generation
developed enrichment culture techniques
developed the first rabies vaccine and treated thousands of individuals
developed enrichment culture techniques
Mycobacterium tuberculosis is very difficult to stain because of the
large amounts of a waxlike lipids present in its cell wall.
Who was the first researcher to provide direct experimental data that supported the germ theory to explain infectious disease?
koch
Kochs postulates in order
pathogen present in all cases of disease; pathogen grown in pure culture; pathogen able to cause disease in healthy host; pathogen re-isolated
Frederick Griffith performed an experiment in which a live culture of avirulent “rough” strain Streptococcus pneumoniae bacteria were mixed with dead cells of virulent “smooth” Streptococcus pneumoniae bacteria. Subsequently, the “rough” bacteria were “transformed” into “smooth” bacteria capable of killing mice. This experiment demonstrated that
molecular genetic information can be transferred between bacterial cells.
Deduce why viruses are excluded from the ribosomal RNA-based tree of life.
Lack RNA
Why is ribosomal RNA especially useful for the study of phylogenetic relationships(evolutionary connections between species)?
highly conserved
Where within a eukaryotic cell is ribosomal RNA (rRNA) synthesized
nucleus
Membrane-enclosed organelles, such as nuclei, lysosomes, endoplasmic reticulum, mitochondria, and chloroplasts
increase structural complexity, help eukaryotes overcome diffusion limitation due to their size, and form specialized environments for specific functions to occur.
The cytoplasmic membrane is termed “semi-permeable” because some substances, like water and alcohols, can pass freely through while others, like sugars, amino acids, and ions, cannot. What molecular characteristics largely determine whether or not a substance can pass through the membrane?
size and hydrophobicity
Teichoic acid molecules in Gram-positive cell walls include phosphate groups. Therefore, they will __________.
bind positive ions like Mg2+ and Ca2+
The main functions of the bacterial cell wall include all of the following EXCEPT __________
actively transporting solutes against the concentration gradient
An endotoxin is
the toxic portion of the LPS.
Type IV pili are involved in
attachment to surfaces, twitching motility, and pathogenesis.
A major function of prokaryotic gas vesicles is to
confer buoyancy on cells by decreasing their densit
When does endospore formation commence?
when bacterial growth ceases due to limitation of an essential nutrient
You find endospores of a particular species. Which of the following is most likely TRUE of this species?
It is a gram-positive bacterium.
Which list contains the correct components of a bacterial flagellum?
filament, hook, basal body
Chemotaxis is a sensory response affecting the rotational direction of the flagellar motor.
true
all eukaryotes have
a membrane-enclosed nucleus.
Given that the cytoplasmic membrane has a fluid dynamic nature, with phospholipids and proteins able to move about within the bilayer structure, what force or structure keeps the membrane from falling apart?
hydrophilic/hydrophobic forces
The energy source derived from the charge separation across the cytoplasmic membrane is referred to as
the proton motive force.
Some membrane proteins are involved in bioenergetic reactions, while others are involved in membrane transport.
true
Transport proteins located in the cytoplasmic membrane are necessary when
nutrient concentration is very low in the environment, transport is needed against the concentration gradient, or diffusion is not possible.
Although the inner leaflet of the gram-negative outer membrane is composed mainly of phospholipids, the outer leaflet of the outer membrane contains
lipopolysaccharides (LPS).
Porins are channels in the outer membranes of gram-positive Bacteria.
false (gram negative)
