Exam Chapters 1, 3, 4, and 5

Microbiology

The study of microscopic organisms.

What is a Micron (Micrometer)?

One millionth of a meter

What does the domain Eukarya contain?

Organisms composed of eukaryotic cells.

Which two domains contain prokaryotes?

Bacteria and Archaea

Which statment correctly compares Archaea and Bacteria?

Archaea are extremophiles; bacteria are found everywhere.

Which groups can have human health implications?

Bacteria, Archaea, Fungi, Protozoa, and acellular infectious agents.

What percentage of bacteria are pathogenic?

Less than 1%

What are fungal cell walls made of?

Chitin

How do fungi reproduce?

Sporulation, producing exospores

How do fungi primarily gain energy?

Degrading dead organic material

How many basic shapes do bacteria have?

Three

Which term describes an organism consisting of a single cell?

Unicellular

Which term describes an organism consisting of multiple cells?

Multicellular

Which term describes an organism or agent that lacks cells?

Accellular

Which statement correctly describes the nucleic acids or composition of viruses, viroids, and prions?

Viruses contain DNA or RNA, viroids contain a short RNA molecule, and prions are made solely of misfolded proteins

What is a microorganism?

A microscopic organism around the micron scale

What is LUCA?

The common ancestral cell from which all cells descended.

Protista is associated with which groups?

a eukaryotic group associated with algae and protozoa.

What are algae?

A type of eukaryotic organism associated with the Protista group

What are fungi?

Eukaryotic organisms that can be single-celled or multicellular

What is a Protist?

An individual organism belonging to the group Protista

How large can Fungi become?

They can be massively large, covering up to 2,200 acres.

What are helminthes?

A group of eukaryotic, cellular organisms

What is peptidoglycan?

A substance found in bacterial cell walls

What is pseudomurein?

A substance usually found in archaeal cell walls

What does microbial physiology study?

Nutrition and metabolism

What does microbial genetics study?

Genes, heredity, and genetic variation

What does microbial biochemistry study?

Enzymes and chemical reactions

What does microbial systematics study?

Classification and nomenclature

What does virology study?

Viruses and subviral particles

What does molecular biology study?

Nucleic acids and protein

What does microbial ecology study?

Microbial diversity/activity in natural habitats and biogeochemistry

What does medical microbiology study?

Infectious disease

What does immunology study?

Immune systems

What does agricultural/soil microbiology study?

Microbial diversity and processes in soil

What does industrial microbiology study?

Large-scale production of antibiotics, alcohol, and other chemicals

What does biotechnology study?

Production of human proteins by genetically engineered microorganisms

What does aquatic microbiology study?

Microbial processes in waters/wastewaters and drinking-water safety

What is the micron scale used to describe in microbiology?

The relative size of cells, viruses, and cellular components

What is the micron scale for microorganisms?

0.1–100 micrometers

Order these from SMALLEST to LARGEST: Viruses, Eukaryotic cells/spores, Cellular components, Bacteria.

Cellular Components, Viruses, Bacteria, Eukaryotic cells/spores

What is true about microorganisms and the history of life?

They are the oldest form of life

What do microorganisms make up?

The largest mass of living material

What major processes are microorganisms responsible for?

Major biogeochemical cycles

Where can microorganisms live?

In places unsuitable for other life forms

What is true about microorganisms and other life forms?

Other life forms require microorganisms for their existence

Approximately how do microbes, mainly bacteria, compare in number to human cells in the human ecosystem?

Microbes out number us 10:1

Approximately how many species of bacteria live inside each person?

10,000

What is the collection of bacteria living inside a person referred to as?

Human microflora

What is true about most of the human microflora?

They are essential for development and good health

What are the three domains? Why did they come from LUCA?

Bacteria, Archaea, Eukarya

Why are Bacteria, Archaea, and Eukarya grouped into the three domains of life?

They all descended from a common ancestral cell called LUCA

What does LUCA stand for?

Last Universal Common Ancestor

Which groups in the Microbial World can have human health implications?

A. Only Bacteria and Archaea
B. Only fungi, protozoa, and helminthes
D. Only viruses and prions

Bacteria, Archaea, Fungi, Protozoa, Helminthes, Viruses, Viroids, and Prions

What is a major difference between bacterial and archaeal cell walls?

Bacteria have peptidoglycan, while Archaea usually have pseudomurein

Which characteristic is especially associated with Archaea?

They can live in extreme environments

Which groups in the Microbial World are acellular?

Viruses, Viroids, and Prions

What biomolecules are Viruses, Viroids and Prions composed of?

Viruses — nucleic acid and protein; Viroids — nucleic acid; Prions — protein

What percentage of microbes cause disease?

Less than 0.1%

What are the two major themes of microbiology?

Understanding basic life processes and applying that knowledge to benefit humans

When did Earth form, and when did the first cells appear?

Earth formed about 4.6 billion years ago, and the first cells appeared about 3.8–3.9 billion years ago.

What was significant about Earth's early atmosphere and the earliest forms of life?

• Earth's atmosphere was anoxic until about 2.3 billion years ago.

• Early metabolisms were exclusively anaerobic.

• Life was exclusively microbial until about 1 billion years ago.