PLTW PBS Principles of Biomedical Science 3.1.4-3.1.7 Quiz WCHS Mrs.McCormick

Etiology (Ex. Flu)

The cause of a disease or a condition (Ex. Influenza Viruses)

How are bacterial species named?

By their genus and species; The first letter of the genus is always capitalized, and both names are either italicized or underlined

What do microbiologists do?

Investigate the growth, structure, development, and other characteristics of microorganisms like bacteria

What is used to culture bacteria?

A petri dish and clear plastic container

What does agar provide for bacteria?

Nutrients and water

Why isn’t a valuation of colony morphology enough to identify the agent responsible for causing a disease?

Because different types of bacteria can have extremely similar looking colonies

Aseptic Technique

The practice and/or process of preventing contamination

Bacterial Colonies

Bacteria grows in groups called colonies, on a growth media called agar

Broth

A clear, nutrient-rich liquid used to culture bacteria, usually in tubes

Morphology

The study of the internal structure of an organism

Binary Fission

A type of asexual reproduction typically observed in prokaryotes and a few single-celled eukaryotes

Gross Morphology

Collective structure of an organism as a whole as a general description of the form and structure of an organism

Margin

Describes the shape of the edge of the colony when magnified

Isolation Streak

The process by which bacteria are streaked onto a plate to form isolated colonies

What kind of bacterial cells are these?

Coccus

What kind of bacterial cells are these?

Bacillus

What kind of bacterial cells are these?

Spirillum

Diplococci

Staphylococci

Gram positive or Gram negative?

Gram positive

Gram positive or Gram negative?

Gram negative

What makes Gram negative more dangerous?

They have an additional layer outside of their petidoglycan layer that can have toxic effects. It can induce a serious immune response that can lead to septic shock

Coccus

Any spherically, or generally round, bacterium; plural is cocci

Bacillus

A rod shaped (cylindrical) bacterium; plural is bacilli

Spirillum

A spiral shaped bacterium

Cell Morphology

The study of the shape, structure, and appearance of cells

Peptidoglycan

A unique, mesh-like polymer composed of sugars and amino acids that forms the cell wall of most bacteria, providing structural support and protection against osmotic pressure

Gram’s Stain

A staining technique used to characterize the cellular structure of Gram positive bacteria. Gram negative bacteria have a lipopolysaccharide coating, which typically makes them more pathogenic

Hans Christian Gram

Microbiologist who discovered that certain stains were preferentially taken up and retained by bacterial cells

Septic Shock

Comes from a serious immune response. It can cause death due to a drop in blood pressure

Decolorization

Ethyl alcohol is applied to the cells. In Gram positive cells, water leaves the cell, blocking the CVI from leaving. In Gram negative cells, the outer membrane gets dissolved and the CVI can leave the cell

Counterstain

Safranin is applied to the cells. In Gram positive cells, safranin penetrates the cell, but is not seen. In Gram negative cells, safranin stains the cell a reddish-pink color

Morbidity refers to…

Having a disease or a symptom of disease, or the rate of disease within a population

Mortality refers to…

The number of deaths in a certain group of people in a certain period of time

What is the purpose of a streak plate?

To isolate single colonies

Is Staph aureus gram negative or positive?

Positive

Does bacteria require a host in order to reproduce?

No

Small circular pieces of DNA that can be exchanged between bacteria; humans don’t have them

Plasmids