Microbiology Chapter 1,3 and 4

Compounds that interfere with the synthesis or structural integrity of peptidoglycan can ______.

result in bursting of a bacterial cell

he cytoplasmic membrane is a(n) __________permeable barrier of the cell.

selectively

Prokaryote

single cell organism consisting of prokaryotic cell; member of bacteria and archaea

Some bacteria are covered with a substance that creates a diffuse irregular layer called a

slime layer

Ribosome

structure involved in protein synthesis

Emerging infectious diseases are those ______.

whose incidence has rapidly increased in the last several decades

The concept of living things arising from vital forces in non-living or decomposing materials was known as which of the following?

Spontaneous Generation

From a bacterium's perspective, what are the advantages of endospore formation?

The endospore withstands dry conditions. Endospores are highly resistant to radiation and heat. The endospore is more resistant to disinfectants.

Periplasm

The gel-like material that fills the region between the cytoplasmic membrane and the outer membrane of Gram-negative bacteria and the cytoplasmic membrane and peptidoglycan layer of at least some gram positive bacteria

What is the main function of lysosomes?

degradation

Pinocytosis and phagocytosis are two of the three examples of

endocytosis

Tyndall and Cohn's experiments in the 1870s showed the presence of a heat-resistant form of bacteria called a(n)

endospore

Which of the following are eukaryotes?

helminths algae protozoa fungi

Domain

highest level of bio classification

____________phase describes the initial phase after bacterial cells are placed into a new environment and are gearing up for cell division, but their numbers have not yet increased.

lag

Bacteria use gas vesicles to float to the surface of water to better access as a source of _____ energy.

light

In which phase of the growth curve is the generation time measured?

log

Transport System

mechanisms used to transport nutrients and other small molecules across the cytoplasmic membrane

During the endocytic process of , the eukaryotic cell takes in liquids by making small invaginations in the membrane, eventually forming a membrane-bound intracellular compartment called an endosome.

pinocytosis

During the endocytic process of _______ the eukaryotic cell takes in liquids by making small invaginations in the membrane, eventually forming a membrane-bound intracellular compartment called an endosome.

pinocytosis

Which of the following is most likely to be a pure culture?

A single colony growing on a streak plate

Flagellum

A type of structure used for cell movement

In what ways is microbial growth in a colony the same as growth in a liquid?

Both involve a lag phase followed by exponential growth; In both cases, cells compete with one another for available nutrients.

Which of the following characterizes the lag phase of a normal bacterial growth curve?

Cells are synthesizing enzymes needed for growth but not increasing in number.

Why are cells growing in a colony on solid media likely to be in many more different phases of growth than cells growing in liquid culture?

Cells in liquid culture experience a relatively uniform environment, so they are much more likely to be in the same phase of growth. Unlike cells on the edge of a colony, those in the center of a colony face depleted levels of nutrients and O2, yielding different phases of growth.

Which device is used to keep cells in a state of constant growth?

Chemostat

Which of the following does not describe interactions of mixed microbial communities?

Conditions in mixed microbial associations are readily reproduced in the laboratory.

Which of the following describes the optimum temperature of a psychrophile relative to a thermophile?

It is lower than a thermophile.

If you inoculated a test tube of cooled liquid agar with an obligate anaerobe and incubated it, where would you expect to find growth?

Only at the bottom of the tube.

Which term is used to describe the process by which cells take up liquids from the surrounding environment?

Pinocytosis

Which term describes a microorganism that has an optimum temperature between -50C and 150C?

Psychrophile

Which of the following correctly describe facultative anaerobes?

They can grow without O2. Their growth is faster when O2 is available.

A batch culture has which of the following characteristics?

Wastes are not removed. It typically involves growth of bacteria or archaea either on agar plates or in tubes or flasks of broths. Nutrients are not renewed. It is a closed system.

An environment with little or no O2 present is called a(n)

anaerobic

From which body site could a facultative anaerobe be isolated?

any of these: deep wound, surface of skin, intestine

The five groups used to categorize microorganisms with respect to growth temperature (psychrophile, psychrotroph, mesophile, thermophile, and hyperthermophile) ______.

are based on optimum growth temperatures.

When bacteria or archaea are grown on agar plates or in tubes or flasks of broth, these closed systems are a______culture. By contrast, cells can also be grown in an open system, or a continuous culture.

batch

What term is used to describe a group of microbes co-existing in polymer-encased communities?

biofilm

An isolated ___________ is a distinct mass of microorganisms appearing on a solid medium, arising from the multiplication of a single cell.

colony

A flexible molecular framework throughout the cytoplasm that anchors organelles and permits shape changes in some cells is called the

cytoskeleton

The log (logarithmic) phase of a normal growth curve is also referred to as the

exponential

Some microorganisms live in harsh environments that kill most other organisms. The term used to describe an organism with this characteristic is

extremophile

Which eukaryotic organelle consists of a series of membrane-bound flattened compartments?

golgi apparatus

A graphical representation of a changing population size over time is called which of the following?

growth curve

The characteristic pattern that shows the changes in size of a bacterial population over time in a broth culture is called a bacterial

growth curve

______ aerobe, or strictly aerobic organism, requires O2 for survival

obligate

Which of the following describes a microbe that must have O2 to survive?

obligate aerobe

Eukaryote

organism composed of one of more eukaryotic cells, members of the domain eukarya

During the endocytic process of __________ the eukaryotic cell engulfs large particles such as bacteria, forming a membrane-bound compartment called a phagosome

phagocytosis

During the endocytic process of _________ the eukaryotic cell engulfs large particles such as bacteria, forming a membrane-bound compartment called a phagosome.

pinocytosis

The dividing bacterial cells can stick to each other. They can form characteristic arrangements such as pairs, chains, or clusters, depending on the _______.

plane of division

If the solute concentration is higher outside the cell than inside the cell, water will diffuse out due to osmosis. This will result in

plasmolysis

Regardless of the pH of the external environment, microbial cells maintain a constant internal pH, typically near neutral. For example, prokaryotes that grow in alkaline conditions bring

protons

Microbial cells must maintain a near-neutral internal pH. Because of this, bacteria that grow in acidic environments have mechanisms to ______.

pump out H+ that enter the cell

A ________ culture contains only ONE species of microorganisms descended from a single cell.

pure

A colony is a distinct mass of microorganisms which develop from a single cell growing on a solid medium.

true

Consider the following environmental factors. Which have the most impact on microbial growth?

water availability temperature oxygen availability pH

Who is Robert Hooke?

an English microscopist who looked at another kind of microorganism and he described how to make a microscope, later they figured the organism was common bread mold

Plasmid

Extrachromosomal DNA molecule that replicates independently of the chromosome

True or false: We could not survive without microorganisms, but they can also be harmful.

True

For the name Streptococcus pyogenes, the first part (Streptococcus) indicates the ______and gives information about the shape of the organism

genus

What does the scientific name of an organism include?

genus and species

If a cell has a nutrient in relative excess, it may accumulate that compound in a storage

granular

Which of the following is true regarding all prokaryotes?

lack a nucleus

eukaryotes

membrane bound organelles transform energy

Which defines spontaneous generation?

Life arose from non-living matter.

_______ showed that flasks containing various broths gave rise to microorganisms even when the flasks were boiled and sealed with a cork.

Louis Pasteur

Why do microorganisms serve as important models for study of higher organisms?

Microorganisms have the same fundamental metabolic and genetic properties as other organisms.

Many members of the Archaea have _________which are sheets of flat proteins or glycoprotein subunits.

S-layers

What is the only shared feature of all microbes?

Small size

Eukaryotic Cell

cell type characterized by a membrane- bound nucleus

Which structure provides strength and rigidity to a cell?

cell wall

In algae, photosynthesis takes place in ______, which have chlorophyll, a green pigment.

chloroplasts

All living organisms are now classified into three different taxonomic units called

domains

The work of John Tyndall and Ferdinand Cohn ______.

explained why some spontaneous generation investigators got different results from those of Pasteur

Gram Positive Bacteria

bacteria that have a cell wall characterized by a thick layer of peptidoglycan, when gram stained these cells are purple

Gram Negative Bacteria

bacteria that have a cell wall characterized by a thin layer or poptidoglycan surrounded by an outer membrane when gram stained these cells are pink

Plague is a _______.

bacterial disease that can be transmitted by fleas

Most bacteria divide by a process called _____ in which one cell enlarges and then divides

binary fission

The cytoplasmic membrane of prokaryotic cells plays a crucial role in transforming energy. This means that the membrane is directly involved in ______.

converting the energy of sunlight or food into ATP

An outbreak of foot-and-mouth disease in England was controlled by ______.

destroying millions of pig, sheep, and cattle

A testable explanation for an observation is called a(n)

hypothesis

In eukaryotes, the genetic material is contained within a membrane-bound structure called the

nucleus

Cells that do not have a membrane-bound nucleus are called _________ cells.

prokayrotic

Which two macromolecules are the major components of cytoplasmic membranes?

proteins and lipids

Algae and protozoa are also referred to as ___________a diverse group that falls within the domain Eukarya.

protist

Which of the following are classified as acellular infectious agents?

prions viruses viroids

None of the Archaea have peptidoglycan in their cell walls. However, some have a similar molecule called

pseudopeptidoglycan

Suppose that the concentration of an ion is higher in the cytoplasm than in the extracellular environment. If the bacterium wants to bring in more of that ion into the cell, which description best describes this type of transport?

requires energy from the cell, moves against the concentration gradient

Although laboratory stocks of the causative agent still exist, humans have eliminated which of the following diseases?

smallpox

Which of the following are functions of membrane transport systems?

Expel wastes from cell Allow nutrients to enter cell

Which of the following molecules can freely pass through the phospholipid bilayer?

water O2 CO2 small hydrophobic compounds

Organisms that populate the human body and which protect it from disease are termed normal

microbiota, flora, biota, or microflora

Compared to the range of types of plants and animals, microbes as a group are ______.

more diverse

Most bacteria have rigid cell walls that contain a unique compound called

peptidoglycan

function of a cell wall

prevent the cell from bursting

In 1749, John Needham produced results that _______ spontaneous generation when he showed that broths that had been boiled and then sealed with a cork _______. Multiple choice question.

support; could still give rise to microorganisms

Unlike the term microorganism, the word microbe also includes ______.

viruses

Because they are often caused by a Helicobacter pylori infection, most stomach ulcers are treatable with ______.

antibiotics

Technically speaking, viruses are not microorganisms because they are not ______.

composed of cells

Which of the following can be characteristics of algae?

unicellular photosynthetic multicellular eukaryotic

Today, the bacteria added to some fermented milk products are advertised as _______.

probiotics

In what ways are archaea similar to bacteria?

- prokaryotic cell structure - energy sources used - shapes and sizes - method of multiplication

Endospore

an extraordinary resistant dormant cell produced by some types of bacteria

Why were Louis Pasteur's experiments with swan-necked flasks so important in helping disprove the theory of spontaneous generation?

They ended arguments that a "vital force" was necessary for spontaneous generation, while preventing contamination from microbes in the air.

Active transport moves compounds against their concentration gradient. The form of energy used for this purpose is either

ATP or adenosinetriphosphate, proton, motive

Some secreted proteins will act as_________outside of the cell and catalyze the breakdown of large macromolecules.

enzymes

Membrane-bound organelles are only found in the cell type called a(n)

eukaryotic cell

Benefits of normal microbiota include all EXCEPT which of the following?

They damage host tissue, allowing our immune system to rid the body of microbes

Chemotaxis

the movement toward or away from a certain chemical within the environment

Mechanisms cells use to bring in nutrients and other small molecules are called

transport systems

_______ showed that flasks containing various broths gave rise to microorganisms even when the flasks were boiled and sealed with a cork.

John Needham

Lipopolysaccharide

Molecule that makes up the outer layer of the outer membrane of Gram-negative bacteria

Who is Antonie Van Leeuwenhoek

dutch fabric merchant who looked at a drop of lake water through a glass lense

True or false: Bacterial components unique to bacteria are potential targets for antibacterial medications used to treat infectious diseases.

true

Which of the following statements about the influenza pandemic of 1918-1919 is true?

More Americans died of influenza in 1918-1919 than were killed in World Wars I and II, and the Korean, Vietnam, and Iraq wars combined.

Which of the following are microscopic fungi?

yeast and molds

Microorganisms are useful in the study of higher life forms for which of the following reasons?

- Microorganisms have the same basic metabolic mechanisms. -Microorganisms multiply quickly. -Microorganisms have the same fundamental genetic properties. - Microorganisms are cheaper to study.

The eukaryotic ribosome found outside the mitochondria is best described as ______.

40S + 60S = 80S

In eukaryotes, a cytoplasmic ribosome is_______and is made up of a small 40S subunit and a large_______subunit

80S or 80 S, 60S or 60 S

_______ is credited with disproving spontaneous generation using broth in swan-neck flasks

Louis Pasteur

Viroid

an acellular infectious agent consisting only of RNA

Peptidoglycan

A macromolecule that provides strength to the cell wall; it is found only in bacteria

Pili

Cell surface structures that allow cells to adhere to certain surfaces; some types are involved in a mechanism of DNA transfer

The two most common examples of endospore-forming genera are

Clostridium and Bacillus

Which of the following about microorganisms is true? Multiple choice question.

We could not survive without them

Capsule

a distinct, thick gelatinous material that surrounds some microorganisms

______ are a large group of photosynthetic eukaryotes that includes the multicellular seaweeds and many single-celled forms.

algea

Virus

an acellular infectious agent consisting of nucleic acid surrounded by a protein coat

Prion

an acellular infectious agent consisting only of protein

The motility of bacteria is typically facilitated by long appendages called

flagella

Cytoplasmic Membrane

A phospholipid bilayer embedded with proteins that surrounds the cytoplasm and defines the boundary of the cell

Life is divided into three domains. What are they?

archaea, eukarya and bacteria

the prokaryotic cell envelope consists of what?

cytoplasmic membrane, capsule, cell wall

As important decomposers, fungi obtain nutrients by ______.

secreting enzymes to degrade organic material in the environment

Which of the following describes how fungi gain energy?

They degrade organic materials.

The principle that microorganisms cause certain diseases is called

Germ Theory of Disease

endospores are ...

are common in soil, and can therefore be found nearly anywhere. are very resistant to damaging conditions, including high heat, toxic chemicals, and UV light. may germinate to produce vegetative cells, which can then multiply.

Prokaryotic Cell

cell type characterized by the lack of a membrane bound nucleus

Eukaryotic cells use the process of ________ to take in substances too large to move through a transport protein.

endocytosis