Medical Microbiology Homework Questions

(T/F) DNA replication occurs in mitosis.

True

Water-based solution that serves as prominent site for biochemical and synthetic activities of the cell

cytoplasmic matrix

Stored nutrients

inclusion body

Acidic polysaccharide attached to the lipids in the plasma membrane in gram-positive cells

lipoteichoic acid

Structure in gram-negative bacteria that is similar in composition to the cell membrane

outer membrane

Of the photosynthetic bacteria, cyanobacteria produce ______ as a product of photosynthesis but the green and purple sulfur bacteria do not produce this substance.

oxygen

Marine algae produce toxins which accumulate in seafood and can cause

severe food poisoning

Loose glycocalyx that protects the cell from dehydration and loss of nutrients

slime layer

This loosely attached, thin mucoid layer protects the cell from drying out or losing nutrients

slime layer

Who was instrumental in disproving the idea of abiogenesis?

Louis Pasteur

Which type of microbiologist would be most likely to work with organisms that are visible to the naked eye?

a parasitologist

Order these bacteria from smallest to largest: 1. a typical virus 2. rickettsias and chlamydias 3. human red blood cell 4. typical bacteria

a typical virus, rickettsias and chlamydias, typical bacteria, human red blood cell

The division of the cytoplasm

cytokinesis

Fine hair-like bristles that help in adhesion to other cells and surfaces

fimbriae

Involved in the horizontal transfer of genetic material

neither flagella nor cilia

The process of assigning names to all levels of an organism's taxonomic ranking

nomenclature

Unique envelope with openings through which ribosomal subunits are transported

nuclear membrane with pores

Site for ribosomal RNA synthesis

nucleolus

Unique bacterial cell wall component that lends rigidity to a cell

peptidoglycan

These tests use DNA to determine the identity of an organism

Genetic techniques

The best understood bacterial cytoskeletons are composed primarily of

actin

Form the cytoskeleton of the cell to stabilize shape

actin filaments

What characteristic has most recently been used to classify eukaryotic organisms and assign them to various taxonomic groups?

analysis of ribosomal RNA

Chromosomes are separated and pulled to the poles by the spindle fibers

anaphase

Infection by organisms that are present on or within the body and delivered to the portal of entry

autoinoculation

These long, coiled threads provide movement to spirochetes

axial filaments

Prokaryotes that were once a part of the kingdom Monera in the Whittaker system of classification

bacteria

Prokaryotic organisms used in genetic engineering due to their simple genetic material

bacteria

What microbe belongs to Kingdom Monera

bacteria

These tests use the presence or absence of biochemical processes and enzymes to group organisms

bacterial physiology/biochemistry

Process that involves the introduction of microbes into the environment to restore stability or to clean up toxic pollutants

bioremediation

Technology that applies the power of microbes toward the manufacture of industrial products, foods, and drugs

biotechnology

The field which uses microbes to produce specific desired products

biotechnology

Composed of a cylinder of microtubules in a 9+2 arrangement

both flagella and cilia

The site of ribosomal RNA synthesis within the nucleus

nucleolus

Most prominent organelle of eukaryotic cells

nucleus

Organelle that houses DNA

nucleus

What microbe belongs to Kingdom Protista

Algae and Protozoa

The genetic material of the cell

Chromosome (DNA)

Why are achaeons extremeophiles?

They are ancient, primitive organisms that adapt well to extreme conditions because they have retained characteristics of the cells that first evolved when Earth's conditions were far more extreme

The primary role of Fimbriae

adhesion to other cells and surfaces

The field which studies the relationships between microbes and domestic plants and animals

agricultural microbiology

Photosynthetic eukaryotes which can be either unicellular or multicellular; multicellular forms to include seaweed

algae

Photosynthetic organisms that may be used to produce alternative fuels

algae

What is the primary role of Pili?

allows for conjugation

This pattern has flagella at both poles of the cell

amphitrichous

The bacterial flagellum moves

by rotation that is powered by the proton motive force.

The correct way to type the scientific name of an organism

capitalize first letter of first word, all in italics

A tightly-bound, sticky glycocalyx composed of repeating polysaccharide and/or protein units

capsule

This layer of polysaccharides and/or proteins is tightly bound to the cell and contributes to the cell's pathogenicity

capsule

The two groups of obligate intracellular bacteria are the _____, usually spread by contact, and the _____, usually transmitted by the bites of arthropods.

chlamydias; rickettsias

Organelle found in plant and algal cells where photosynthesis takes place

chloroplast

Order the following to reflect the generalized anatomy of bacterial cells from innermost to outermost 1. cell membrane 2. cell wall 3. glycocalyx 4. cytoplasmic matrix

cytoplasmic matrix, cell membrane, cell wall, glycocalyx

The highest hierarchical level

domains

Outermost boundary of most eukaryotic cells that plays a role in protection, adherence, and reception of signals

glycocalyx

This is the general term which describes all the various coatings covering the surface of the cell

glycocalyx

Bacterial species are defined in a fundamentally different way than mammalian species are. This is because

mammals reproduce sexually while bacteria reproduce asexually

A taxonomical outline of bacterial species based on shared evolutionary histories would be described as a

phylogenetic system

An elongated, hollow appendage used in DNA transfers between cells

pilus

The cell membrane is composed of __________.

proteins dispersed throughout a phospholipid bilayer

Eukaryotes which are always unicellular

protozoa

While examining a sample of pond water you note a cell covered with thousands of minute hair-like extensions which it uses to propel itself through the water. This cell can immediately be classified as a/an

protozoan

An organism that lives in very cold conditions, including temperatures below freezing

psychrophile

Composed of RNA and protein, this structure synthesizes new proteins

ribosome

Protein "factories"

ribosomes

Organelle that possesses ribosomes for protein synthesis

rough endoplasmic reticulum

Closed tubular network without ribosomes involved in nutrient processing and the synthesis of lipids and other molecules

smooth endoplasmic reticulum

The ______ level of bacterial organisms refers to a group of organisms that all share the same traits while the subspecies level refers to the variation or differences of individual cells within that group.

species

Ribosomes function primarily to

synthesize proteins

The development that led to the new three domain system of classification

the discovery of rRNA leading to an understanding of archaeons

What makes up the specific name of an organism?

the genus name and then the species name

The primary function of the cell membrane is

to regulate the transport of molecules in and out of the cell

Structures that are picked up by the forming face of the Golgi apparatus

transitional vesicles

(T/F) Cyanobacteria are of interest (and are named for) their ability to degrade areas contaminated with cyanide.

true

Organelle used for locomotion in some cells

flagellum

Specialized for appendage used for motility

flagellum

The eukaryotic ribosome is a(n) _____ ribosome, composed of 40S and 60S subunits.

80S

What is the correct order of the phases of the cell cycle?

G1 -> S -> G2 -> M

The study of molds and yeast is called

mycology

The field dedicated to monitoring and controlling the spread of disease within a population

Public health microbiology and epidemiology

Bilayer of phospholipids in which protein molecules are embedded

cell membrane

Phospholipid bilayer of the cell

cell membrane

The innermost layer of the bacterial cell envelope

cell membrane

A semirigid casing that provides structural support and shape for the cell

cell wall

Rigid structure found in fungal and plant cells which provides structure and support

cell wall

Organelles that play a role in chromosome separation during cell division

centrioles

The structure which contains the essential DNA of the cell

chromosome

Found in certain protozoa and animal cells; can serve as feeding/filtering structure

cilia

Grouping organisms based on their evolutionary relationships is the process of ______, which is part of taxonomy.

classification

The process of grouping organisms into groups which reflect the history and evolutionary relatedness of those organisms

classification

Receive chemically modified proteins from the Golgi apparatus

condensing vesicles

This arrangement is formed when two rod-shaped bacteria divide on the transverse plane and do not separate

diplobacilli

This arrangement is formed when a coccus divides on a single plane and the two daughter cells remain attached

diplococci

The field which is concerned with food borne diseases as well as food and beverage production

food and dairy microbiology

Eukaryotes which can be either unicellular or multicellular; multicellular forms include mushrooms

fungi

Used by humans in the production of some antibiotics

fungi

What microbe belongs to Kingdom Myceteae

fungi

Newer technology that manipulates the genetics of microbes, plants, and animals to create new products and genetically modified organisms (GMOs)

genetic engineering

The field which manipulates DNA of an organism to create a new organism with a desires trait

genetic engineering

You are studying a new variant of a eukaryotic cell. The variant cell has mutated so that it no longer attaches well to surfaces or initiates the formation of a biofilm. The mutation in this cell has most likely affected the _____.

glycocalyx

Site of protein modification

golgi apparatus

Bacterial cell type that stains red upon Gram staining

gram-negative cell

Bacterial cell type that has a strong cell wall due to the presence of a thick peptidoglycan layer

gram-positive cell

Eukaryotes whose adult forms are always multicellular

helminths

An organism that lives in extremely hot temperatures such as the hot springs of Yellowstone National Park

hyperthermophile

The process of determining the characteristics of an organism which will be used to place the organism into its taxonomic ranks

identification

The field which studies the protective reactions to microbial infections, examples include blood testing and vaccination

immunology

This structure stores nutrients during periods of ample resources to compensate for times when nutrients are scarce

inclusion bodies

A scientist observes that all people who contract a painful skin rash known as shingles have previously in their lifetime been infected with chicken pox. He theorizes that the virus that causes chicken pox is the same virus that cause shingles. What type of reasoning is being displayed in this case?

inductive reasoning

Active metabolic period before mitosis occurs

interphase

The stages of cell division in order

interphase, prophase, metaphase, anaphase, and telophase

Molecules embedded in the cell membrane of all bacterial cells

membrane proteins

Increases surface area of the cell membrane for its activities

mesosome

Duplicated chromosomes are attached at the centromere

metaphase

An organism that lives in anaerobic environments and converts carbon dioxide and hydrogen into methane

methanogen

Actin filaments that are involved in cytoplasmic streaming and locomotion

microfilaments

Spindle fibers are an example of these cytoskeletal elements

microtubules

Folded surface of finger-like projections that increases the cell surface area

microvilli

This arrangement is formed when bacilli that are attached end to end fold back on each other to form rows of side-by-side cells

palisades arrangement

While the vast majority of microorganisms are not harmful to humans, those that are are referred to as

pathogens

The molecule primarily responsible for the strength and stability of the bacterial cell wall is

peptidoglycan

The structure which contains the nonessential DNA of the cell

plasmid

Variation in cell shape and size within a single species

pleomorphism

This type of flagella can be found at either or both ends of a cell

polar

Membrane channels that span the outer membrane and regulate transport into the cell

porin proteins

Chromosomes begin to condense and take on a threadlike appearance

prophase

What is the correct order of the phases of mitosis?

prophase -> metaphase -> anaphase -> telophase

When all the flagella on a cell rotate in a counterclockwise fashion the cell is propelled forward in a movement known as a _____, but when the flagella reverse direction, the cell stops and changes course in an action known as a _____.

run; tumble

What is found in gram-positive cells?

telchoic acid

Chromosomes are located in each pole of the cell and division into two daughter cells occurs

telophase

This arrangement is formed when a coccus divides on perpendicular planes and results in four cocci being attached as a cluster of cells

tetrad

Require electron microscopy for visualization

viruses

A lipid and protein lining that surrounds the cytoplasm and restricts movement of materials in/out of the cell

cell membrane

Process in which the infectious stage of the helminth is passed from one host to another

cross-infection

Excess nutrients that the cell may store for later use may be found within

cytoplasmic granules

This structure is a network of protein polymers that helps stabilize the shape of the cell from within

cytoskeleton

What best characterizes endospores?

dormant, tough, and non-reproductive structure produced by certain gram (+) bacteria

An _________ disease is a new disease being reported in increasing numbers within the population while a ______________ disease is a disease which has existed in the past but is currently seeing increasing numbers of cases.

emerging; re-emerging

The algae are photosynthetic, eukaryotic protists that are grouped into _____ (no cell wall and motile by flagella), _____ (single-celled with golden chloroplasts and intricate cell walls), _____ (cause "red tide"), kelp, red seaweeds and green algae.

euglenids; diatoms; dinoflagellates

Organisms that are more closely related to archaea than bacteria

eukarya

These hatch and release larvae in the intestine

fertile egg

Composed of a filament, hook and basal body, these cell appendages provide movement to the cell

flagella

Found in certain protozoa and some algae

flagella

This structure stores inorganic compounds, such as sulfur and polyphosphate

granules

An organism that lives in an environment that contains high amounts of salt such as the Dead Sea

halophile

What is found in gram-negative cells?

lipopolysaccharide; outer membrane

Molecules known as endotoxin; stimulate fever and shock reactions in gram-negative infections

lipopolysaccharides

This pattern has groups of flagella all originating from the same point on the cell

lophotrichous

Vesicle originating from the Golgi apparatus involved in intracellular digestion

lysosome

Other than maintaining the shape of the cell, what is the primary function of the cell wall, and which component contributes most to this function?

maintaining strength; peptidoglycan

Organelle that generates ATP energy from glucose

mitochondrion

This pattern has one flagellum attached at one end of the cell

monotrichous

These tests use cell shape and Gram reaction to classify organisms

morphology

What is found in both gram-positive and gram-negative cells?

peptidoglycan; cell membrane

This pattern consists of flagella randomly distributed around the cell

peritrichous

Organelle originating from the nuclear envelope and containing major organelles of protein synthesis

rough endoplasmic reticulum with ribosomes

Structure from the Golgi apparatus that can release their contents to the cell's exterior via exocytosis

secretory vesicle

Process in which the host infects itself, typically by transferring infective eggs from the environment to the mouth with hands

self-infection

These tests use antibody reactions to identify an organism or to determine relatedness

serological analysis

This arrangement is formed when rod-shaped bacteria divide multiple times on their transverse planes and do not separate therefore the cells continue to be attached to each other

streptobacilli

Describes the system of arranging and naming organisms

taxonomy

Most protozoa have a motile, feeding stage known as a(n) _____ which, in some protozoa, alternates with a resting state known as a(n) _____.

trophozoite; cyst

The cell ______ is found in fungi and algae to provide structure and support while the cell ______ is found in all eukaryotic cells, is composed of phospholipids, proteins and sterols, and separates the internal cell components from the external environment.

wall; membrane