Humans and the Microbial World

Protists

Algae and protozoa

Microbes

Any microscopic organism. Mainly bacteria, protists, some fungi, and even some tiny multi-cellular organisms

Members of which domain can be infected by viruses?

Archaea, Eukarya, and Bacteria

Helminths

Are worms that live at the expense of a host (parasites)

What type of microorganisms lack the membrane-bound organelles?

Bacteria and archaea

What is the difference between archaea and bacteria?

Bacteria possess peptidoglycan in their cell walls whereas archaea does not

What are the three domains?

Bacteria, Archaea, Eukarya

Spontaneous Generation

Based on the belief that life arises spontaneously from non-living material

What is the process in which microbes carry out the decomposition of harmful chemicals?

Bioremediation

How does fungi obtain energy?

By secreting enzymes onto organic materials, and then absorb the released nutrients

What is the chemical composition of archaea?

Cell walls lack peptidoglycan Ribosomal RNA sequences different significantly from bacteria

Prokaryotic

Cells don't have a membrane-bound nucleus

Eukaryotic

Cells that have membrane-bound nucleus and organelles

What do chloroplasts contain?

Chlorophyll or other pigments that give characteristics colors

In algae, photosynthesis takes place where?

Chloroplasts

Microorganisms in the Environment

1. Recycling of nutrients 2. Nitrogen Fixation 3. Decomposers of Material

How many years did it take to disprove spontaneous generation?

200 years

Endospores

Heat resistant forms of bacteria

Host

Infect living cells

What can the evolution of disease agents lead to?

Infect new host, cause different types of damage to host, and become resistant to antibiotics

Prions are...?

Infectious proteins

What describes a viroid?

It consists of a single short piece of RNA

Mushroom

Macroscopic reproductive structure characteristics of some fungi

Diseases that have become more common

Malaria Tuberculosis

Normal Microbiota

Microbes normally present in and on the human body

Germ Theory of Disease

Microorganisms cause disease

Infectious proteins

Misfolded versions of normal cellular proteins found in brain

Compared to the diversity of plants and animals, microbes as a group are....?

More diverse

What are some examples of helminths?

Roundworms, tapeworms, and flukes

Without microorganisms, substances required for human life such as O2 and organic nitrogen would...?

Run out

Eukarya

Single-celled or multicellular eukaryotes

To indicate slight differences, members of the same species may be given what?

Strain designations

Solid, repeatable, extensive amounts of scientific evidence can lead to what?

Theory

Why were Louis Pasteurs 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

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

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

Algae are...

Multicellular, photosynthetic eukaryotes Single-celled, photosynthetic eukaryotes

Where does algae usually live?

Near the surface of water or in moist habitats

As important decomposers, fungi obtain nutrients by...?

Secreting enzymes to degrade organic material in the environment

Bacteria

Single-celled prokaryotes

Archaea

Single-celled prokaryotes similar in size, shape, and share many properties to bacteria

Eukaryotic organisms can be...?

Singled-celled or multicelled

Prions are misfolded proteins that cause what?

The normal version of the protein to also misfold

Biogenesis

The production of living things comes from other living things

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

Pathogens

Disease causing agents

Algae

Diverse group of photosynthetic eukaryotes. Single-celled or multi-celled.

Protozoa

Diverse group of single-celled eukaryotes. Complex, larger than bacteria.

Fungi

Diverse group ranging from single-celled yeasts to multicellular molds

The "old friends" hypothesis suggests that....?

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

Newly Recognized Diseases

Ebola virus Disease MERS/SARS Influenza (certain types) Lyme Disease AIDS Hantavirus Pulmonary Syndrome Mad Cow Disease

Characteristics of archaea that are similar to bacteria include?

Energy sources used, Shapes, Prokaryotic cell structure, and Method of multiplication

The cells of which group of microorganisms contain membrane-bound organelles?

Eukarya

What is the domain of organisms whose cells have a nucleus and various organelles?

Eukarya

What is true regarding scientific names?

Genus names are commonly abbreviated Scientific names are italicized or underlined

Organisms that populate the human body and which protect it from disease are called what?

Normal Flora

Viruses

Nucleic acid packaged in protein coat. Infect living cells

Emerging Infectious Diseases (EIDs)

One that has become more common in last 35 years

Microorganisms

Organisms too small to be seen with the naked eye

Like plants, some microorganisms....?

Produce oxygen Are photosynthetic

Genetic Engineering

Production of medication by certain microorganisms

What are the two basic cell structures?

Prokaryotic and Eukaryotic

What is true of ALL prokaryotes?

They lack a nucleus

True or false? Studies indicate that normal microbiota of the body may affect brain chemistry

True

True or false? Travelers and immigrants can contribute to disease emergence

True

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

True

True or false? Without microorganisms, we would run out of nutrients

True

Biotechnology

Use of microorganisms and biomedical techniques to solve practical problems

Bioremediation

Use of microorganisms to breakdown

The human Microbiome Project does what?

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

What is true regarding to viruses?

Viruses can only multiply within the host Outside of host cells, viruses are inactive

What is classified as an acellular infectious agents?

Viruses, viroids, and prions

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

Composed of cells

Viroids

Consist of only a single short piece of RNA. Cause plant disease. No evidence they cause disease in humans.

Prions

Consist only of protein. Misfold versions of normal cellular proteins that cause the normal versions misfold.