Exam 1 Flashcards
the supposed production of living organisms from nonliving matter
Spontaneous generation (abiogenesis)
it asserts that living things can only be produced by another living thing
Biogenesis
free from reproductive spores or germs; as, a sterile fluid.
Sterile
is a method designed to prevent contamination from microorganisms
Aseptic techniques
states that many diseases are caused by microorganisms
Germ theory of disease
discovered bacteria, and invented the microscope. Known as the “father of microbiology.”
Antonie van Leeuwenhoek
discovered that microbes were responsible for souring alcohol and came up with the process of pasteurization, where bacteria is destroyed by heating beverages and then allowing them to cool. His work in germ theory also led him and his team to create vaccinations for anthrax and rabies
Louis Pasteur
American physician First documented recommendation of hand washing by healthcare workers to prevent disease
Oliver Wendell Holmes
Hungarian physician who first instituted to wash hands with bleach having tremendous results
Ignaz Semmelweis
made surgery much safer with the use of phenol to kill micro-organisms on skin of patients and surgical tools
Joseph Lister
also the most important microbiologist developing the bacteriological techniques (agar, petri dish) proving micro-organisms caused harm. Experimental verification of the “germ theory of disease” Proved anthrax was caused by micro-organisms and discovered mycobacterium tuberculosis.
Robert Koch
Describe the structure of DNA -
DNA is made up of six smaller molecules – a five carbon sugar called deoxyribose, a phosphate molecule and four different nitrogenous bases (adenine, thymine, cytosine and guanine).
Describe the structure of RNA -
The basic components of RNA are the same than for DNA (see the DNA page) with two major differences. The pyrimidine base uracil replace thymine and ribose replace deoxyribose (see the sugars, purines and pyrimidines pages).
The process that causes a protein to lose its shape
denaturing the protein
prokaryotic cells, live in temperate climates.
Bacteria
ancient bacteria, live in unusual or hard environments
Archaea
Eukaryotic, single celled, classified by motility , many free living, some cause disease
Protozoa
eukaryotic, yeasts (unicellular), molds (multicellular)
Fungi
eukaryotic, multicellular, parasitic worms, adults macroscopic, eggs and larva microscopic.
Helminths
eukaryotic, microscopic plants, unicellular or multicellular, does not cause disease, photosynthesis.
Algae
acellular, insert outside host cell, made of a protein coat and nucleic acid, most common cause of human infection
Viruses
acellular, abnormally folded proteins, infects cells and causes normal proteins to fold abnormally, causes spongiform encephalopathies (mad cow)
Prions
acellular, single stranded pieces of RNA that are infectious and can cause disease, usually infects plants, potato spindle tuber and apple scar skin are a product of this microbe.
Viroid
microbes that live on or in the body and do not cause harm and are often beneficial to the body. (when they are in the correct location)
Normal Flora
used to produce products or to improve organisms.
Biotechnology
manipulation of the genes of organisms.
Genetic engineering
transferring genetic material from one organism to another.
Recombinant DNA technology
using microbes to stabilize ecosystems or clean up waste or pollution.
Bioremediation
cause disease in all people.
Primary Pathogen
cause disease in immunocompromised people or when put in the wrong place or when normal flora is lost.
Opportunistic pathogen
bacteria and archaea, 10x smaller than eukaryotic cells, lack organelles, can still have complex structure, can engage in all activities a eukaryotic cell can, all microorganisms.
Prokaryotic cells
animals/plants/fungi/protozoans, have organelles (ribosomes, nucleus, mitochondria), some microorganisms, some macroorganisms.
Eukaryotic cells
the science of classifying living things.
Taxonomy
the assignment of scientific names to various taxonomic categories and to individual organisms.
Nomenclature
prokaryotic, modern bacteria
Bacteria
prokaryotic, ancient bacteria
Archaea
eukaryotic, Protista/fungi/plantae/Animalia
Eukarya
Protisita -
protozoans
Fungi -
molds, and yeasts, not photosynthetic
Plantae -
algae, are photosynthetic
Animalia -
Helminths
variation in the size and shape of cells of a single species due to nutritional and genetic differences.
Plemorphic
aggregated groups of microbes that form as a layer with associated organic materials.
Biofilms
Coccus shapes >
single (1), diplococci (2), streptococci (long chains), tetrads (four), sarcina (eight), staphylococci (irregular groups)
Bacillus shapes >
single (1), diplobacilli (2), streptobacilli (long chains)
comma shaped
Vibrio
ridged, corkscrew shaped cells, motile through flagella
Spirillum
flexible, corkscrew shaped cells, motile with axial filament
Spirochete
branching
Filamentous
Structure: Capsule: tight fitting coating of molecules external to cell wall/ or Slim layer: loose fitting and diffuse coating of molecules external to cell wall. Function: Adherence, protection, and receptor. Clinical Significance: Infection, but only with capsule form. The capsule inhibits phagocytosis. Genes can also be transferred between the organisms.
Glycocalyx
Structure: Fine hair like bristles extending from the surface of the cell. Function: helps in adhesion to other cells and surfaces. Clinical Significance: Potential target for antibiotics. They form fragments that bind antibody molecules & inactivate them.
Fimbriae
Structure: An appendage. Function: Used for drawing another bacterium close in order to transfer DNA to it. Clinical Significance: They often contain genes that allow bacteria to become more virulent.
Pili
Structure: An appendage. Function: Motility. Clinical Significance: since flagella is motile it helps opportunistic infections, escape from host defense, and systemic infection.
Flagella
Structure: Appendage that is enclosed in the space between the cell wall and the cytoplasmic membrane. Function: Motility which is corkscrew like movement. Clinical Significance: It can corkscrew into tissues normal bacteria cannot get to, and it can get into the blood. Both of these abilities help cause infection
Axial filament
Structure: Thin sheet of lipid and protein that surrounds the cytoplasm. Function: Controls that flow of materials in and out of the cell pool. Clinical Significance: Susceptibility. Primary target for antibiotics. Inhibits DNA replication. Destroys the ability to produce energy. Causes loss of membrane integrity and destruction of the cell.
Plasma membrane
Structure: Composed of dense DNA molecules. Function: DNA directs all genetics and heredity of the cell and codes for all proteins. Clinical significance:
Nucleoid and bacterial chromosome -
Structure: Double stranded DNA circle. Function: Contains extra genes. Clinical Significance: Carry genes for toxins, and is antibiotic resistant.
Plasmids
Structure: Tiny particles composed of protein and RNA. Function: Protein synthesis. Clinical Significance: Major target for antibiotics, because they will cause inhibition of protein synthesis which is lethal to the cell.
Ribosomes
Structure: Dense crystal or particle. Function: Stores nutrients such as fats, phosphates, or glycogen that can be used when needed. Clinical Significance: NONE
Inclusion bodies
Structure: Dormant body formed within some bacteria. Function: Allows for survival in adverse conditions. Clinical Significance: Infection. Resistant to antibiotics, and heat. Is also resistant to almost all disinfectants, and antiseptics.
Endospores
Atrichous
no flagella
Monotrichous
single flagellum
Lophotrichous
small branches or tufts of flagella emerging from the site.
Amphitrichous
flagella at both poles of the cell.
flagella are dispersed randomly all over the surface of the cell.
Peritrichous
Structure: a semirigid casing. Function: support and shape for the cell. Clinical Significance: Target for antibiotic, which ends up disrupting the integrity and causing cell lysis
Cell wall
- Thick, homogenous sheet of peptidoglycan made of many layers.
- Contains teichoic acid and lipoteichoic acid that joins the layers.
Gram-positive cell walls
- Single sheet of peptidoglycan
- Thinness gives gram-negative cells great flexibility and sensitivity to lysis.
- Contain an outer membrane – made of lipoproteins and lipopolysaccharides. Lipid A (endotoxin), and porin proteins (they only allow certain chemicals to penetrate.)
Gram-negative cell walls
Mycobacterium
• Cell walls contain mycolic acid.
• Mycolic acid – a waxy material that contributes to the pathogenicity of the bacteria, due to its resistance to certain chemicals, dyes, and to digestion by phagocytic cells.
Acid-fast bacteria
Mycoplasmas
• Naturally lack a cell wall
• Sterols in the plasma membrane stablilze the cell against lysis.
• Mycoplasma pneumoniae – “walking pneumonia”
Cell-Wall-Deficient Bacteria
body or colony of mold.
Mycelium
threadlike cells that form from the bodies of molds.
Hyphae