Microbiology exam 1

Infection

The invasion and growth of germs in body

Isolation

The separation of microbial cells by serial dilution or mechanical dispersion on solid media to create discrete colonies

Contamination

The unintentional introduction of unwanted microorganisms into a sample environment

Inoculation

The implantation of microorganisms into or upon culture media

What is an archaea?

Single celled microorganisms with structures similar to bacteria

How does a colony grow?

Mixed culture

A container growing two or more different known species of microbes

Pathogen

Any agent; usually a virus, bacterium, fungus, protozoan, or helminth that infects body tissues and causes disease

Parasite

A close interaction in which one organism from which it obtains nutrients and receives protection, the parasite produces some degree of harm to the host

Eukaryotes

An organism whose cells contain a well defined nucleus surrounded by a membrane along with other membrane bound organelles; presence of a nucleus

Endospore

A small dormant resistant derivative of a bacterial cell that germinates under favorable growth conditions into a vegetative cell

Electron

A negatively charged subatomic particle that is distributed around the nucleus in an atom

Mass

Measurement that reflects the number of protons and neutrons in an atom of a particular element

Matter

All tangible materials that occupy space and have mass

Prokaryote

Small cell lacking special structures such as a nucleus and organelles

What are decomposers?

A consumer that feeds on organic matter from the bodies of dead organisms

What is a nucleotide made up of?

Nitrogen containing base, 5 carbon sugar molecule, and a phosphate group; adenine guanine thymine cytosine and uracil

Where do you find protons neutrons and electrons?

In the center of the atom, making up the nucleus while the electrons are found outside orbiting around.

What type of charge does a proton have?

Positive electrical charge (+1)

What type of charge does a neutron have?

No charge

What type of charge does an electron have ?

Negative charge

What’s peptidoglycan?

A network of polysaccharide chains cross linked by short peptides that form the rigid part of bacterial cell walls

Where do you find peptidoglycan?

In the cell walls of most bacteria

Glycocalyx

A filamentous network of carbohydrate rich molecules that coat cells

What makes you the glycocalyx?

A negatively charged network of proteoglycans, glycoproteins, and glycolipids

Where do you find the glycocalyx?

On the outer surface of nearly all cell membranes

What is a contaminant?

An impurity; any undesirable material or organism. A culture into which unknown microbes have been introduced is contaminated

Pure culture

A container growing a single species of microbe who’s identity is known

Louis Pasteur Main accomplishments

Discovered the process of pasteurization, vaccines, and germ theory

Jospeh Lister main accomplishment

Helped with the introduction of germ theory, developed antiseptic techniques for cleaning; kill germs and prevent infections

Antonie Leeuwenhoek main accomplishments

Laid the foundations of plant anatomy anf animal reproduction; father of microbiology because of his discoveries using microscopes he built and designed

Ignaz Semmelweis main accomplishments

Introduced antisepsis handwashing protocols; discovered the cause of fever and his discovery helped with infection control

Robert Koch main accomplishments

Discovered the bacteria that causes certain sicknesses; like tuberculosis

Selective media

A type of culture medium designed to allow growth of only certain desired microorganisms

Differential medium

Type of culture medium designed to visually distinguish between different types of microorganisms based on their biochemical properties

What does cilia do?

Moves fluids or particles across the cell surface

What does fimbriae do?

Provide adhesion; bind to specific receptors of host cells

What does flagella do?

Helps cells move, assist in cell movement

What do pili do?

Short hair like structures of bacteria that help with adhesion

Places you’d find eukaryote

Animals, plants, fungi, protists, most algae

Places you’d find archaea bacteria

Live in harsh habitats; hot temperatures, salt lakes, acidic soils

Hello thx

Parasitic worms that live in and feed off of other organisms

Mold

The filamentous fungi composed of elongate hyphae

Spontaneous generation

Early belief that living things arose from vital forces present in nonliving or decomposing matter

What do you do to culture microorganisms?

Prepare a growth medium with the necessary nutrients and introduce a sample containing the microorganisms you want to grow, incubate the culture at optimal temperature to allow multiplication and form visible colonies

What do you use a microscope for?

To see objects that are too small to be seen with the naked eye

Steps in the scientific method

• Observation

• Ask

• Hypothesis

• Test prediction

• Analyze

• Record data

• Conclusion

Parasite

An organism that lives on or in a ghost organism and gets its food from or at an expense of its host

Who discovered heat resistant bacterial spores?

Ferdinand Cohn

Simple stain

Positive staining teachings that uses a single dye to add color to cells so that they are easier to see

Negative stain

A staining technique that renders the background opaque or colored and leaves the object unstained so that it is outlined as a colorless area

Gram stain

Differential stain for bacteria useful in identification and taxonomy; positive appears purple and negative appears red

Capsule stain

Staining the outside of the cell, the outer space becomes visible

What is the universal solvent

Water

Why do you stain cells

It makes them more visible, allowing for better observation

Five steps of microbial culture (Five I’s)

• Inoculation

• Incubation

• Isolation

• Inspection

• Identification

Taxonomy order: Biggest to Narrow

Domain, Kingdom, Phylum, Class, Order, Family, Genus, species

Magnification

The process of making an object appear larger than it actually is

Resolution

The ability of the microscope to distinguish between two closely spaced points on a specimen

Resolving power

The microscopes ability to distinguish between two closely spaced objects; see in better detail

DNA

Deoxyribonucleic acid; contains genetic information for development and functioning of an organism

RNA

Ribonucleic acid is a molecule that carries genetic information and helps make proteins in living cells

Element

A pure substance composed of only one type of atom

Ion

An atom or molecule that carries an electrical change; meaning it lost or gained electrons

Molecule

The smallest unit of a substance and composed of two or more atoms held together by chemical bonds

Compound

Substance made up of two or more different elements are chemically combined in a fixed

Ribosome

A small cellular structure composed of RNA and protein that acts as the site for protein synthesis

What does the nucleus do?

Acts as the control center and stores genetic material

What does the nucleoid do?

Controls the activity and reproduction of the cell housing and managing the genetic material needed for DNA replication and transcription

What structure do all bacteria have ?

Cell membrane, Cytoplasm, ribosomes, cell wall, and a nucleoid

What does the cell use protein for?

Structural support, chemical reactions as enzymes, molecule transport

What do cells use ATP for?

A primary energy source

What do cells use phospholipid bilayer for?

To act as a selective barrier, controlling what goes in and out of the cell

Plasmids

A small piece of DNA that exists separately from a cells main chromosome and can replicate; they carry genes providing traits

Cell membrane

Acts as a barrier that surrounds a cell

Inclusions

Non living substances found within the cytoplasm of a cell; function as storage sites for nutrients and secretory products or pigment granules