Microbio Ch 1

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The "Old Friends" hypothesis suggests that _____

Early exposure to certain microorganisms helps protect individuals from allergies, asthma, and some other diseases

How microorganisms are useful in the study of higher life forms

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

What can viruses infect?

Plants, Animals, Protists, Bacteria, and Fungi

Consider the Human Microbiome Project begun in 2007. The term microbiome has which two overlapping meanings?

The microbial community itself, and the total genetic content of a microbial community

What is biotechnology?

The use of microorganisms to solve practical problems

How do fungi gain energy?

They degrade organic materials with enzymes

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.

Bacteria that are rod shaped are called

bacilli/bacillus

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

Peptidoglycan is found in the _____

cell walls of bacteria

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

chloroplasts

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

composed of cells

Cocci that divide in perpendicular planes form _____

cubical packets

The microscopic filaments of molds are called ______

hyphae

examples of emerging infections diseases

mad cow disease, Zika, Lyme disease, Ebola

The Golden Age of Microbiology is the period in which _____

many disease-causing microorganisms were discovered

The Germ Theory of Disease states that _____

microorganisms cause certain diseases

A mycelium is a(n) _____

network of hyphae produced by molds

The genetic material in prokaryotic cells is located in a region of the cytoplasm called the

nucleoid

Characteristics of viroids

It consists of RNA and can infect plants

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

John Needham

Which defines spontaneous generation?

Life arose from non-living matter

Bacteria that are sphere-shaped are called

cocci/coccus

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

peptidoglycan

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

Commercially valuable products from microorganisms include _______, which is used in the manufacture of disposable diapers and plastics

polyhydroxybutyrate

Spongiform encephalopathies are caused by infectious proteins. This information indicates that the infectious agent is a(n)

prion

Which are the most resistant to sterilization techniques?

prions

Lazzaro Spallanzani's experiments of 1776 showed that flasks of broths that had been boiled for long periods of time and sealed tight ______

remained free of microorganisms

Although archaea and bacteria differ in a number of important characteristics, it was ultimately significant differences in their _______ that provided the basis for separating the two groups of prokaryotes into different domains.

ribosomal RNA sequences

characteristics of protozoa?

single-celled eukaryotes, ingest organic materials as food sources

The species names of Escherichia coli and Escherichia vulneris reflect the _____

site where the organisms may be found

If Pasteur had performed his spontaneous generation experiments in a horse stable, his results would likely have ______

supported the idea of spontaneous generation

Slight genetic variations among members of the same species are indicated by assigning

strain designation

Escherichia coli K12 and Escherichia coli B belong to different _____

strains

What did the the Human Microbiome Project do?

used DNA sequencing to characterize microbial communities that inhabit the human body

Bioremediation refers to _____

using bacteria to clean up pollutants

You discover an agent that multiplies in plant cells and consists of only a single RNA molecule. It must be a(n) ______

viroid

Unlike the term microorganism, the word microbe also includes _____

viruses

The microbial world includes three main agents that cannot reproduce independently and are thus considered non-living. These are the...

viruses, viroids, and prions

Prions are misfolded proteins that cause ______

the normal version of the protein to also misfold

Microscopic fungi that are single-celled are called ______, and that that are multicellular and filamentous are termed _______

yeasts; molds

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

support; could still give rise to microorganisms

The genus name Escherichia originates from _____

the name of the scientist

In research, a model organism should _____

Function in a manner similar to other organisms

Viruses are ______

obligate intracellular parasites

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

protists

John Tyndall's experiments in the 1870s showed that microorganisms remained in some broths even after boiling for 5 hours. This was later explained by presence of endospores in his broths. Pasteur might have had results similar to Tyndall's if he had used which two materials to make his broths?

soil and hay

What is a helminth?

a worm, some of which are parasitic

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

endospore

In what ways are archaea similar to bacteria?

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

Which are produced by microorganisms?

ethanol and antibiotics

characteristics of algae?

eukaryotic, photosynthetic, unicellular or multicellular

A bacterium that is pleomorphic is one that _____

exists in different shapes

The work of John Tyndall and Ferdinand Cohn ______

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

Who experimented with raw meat, worms, and flies in an attempt to disprove spontaneous generation?

francesco redi

Characteristics of viruses

Consist of nucleic acid and protein, acellular, and nonliving

Because less than 1% of microorganisms can currently be grown in the laboratory, most of what we know about the other 99% comes from _____

DNA sequencing

Prions are _______ that cause a number of diseases in ______

infectious proteins; animals

What killed more people in 1918-1919 than died in World Wars I and II and the Korean, Vietnam, and Iraq wars combined

influenza

Protozoa are _______ eukaryotes that _______ a rigid cell wall

unicellular; lack


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