microbiology chapter one - review sheet final

microbiology

the study of organisms too small to see with the naked eye

the five types of microorganisms

bacteria, viruses, fungi, protozoa, and algae. (helminths as well but they aren’t technically micro)

pathogen

a microorganism that causes disease within a host

• includes viruses, bacteria’s, fungi, protozoa, helminths

• nearly 2,000 microbes are known to cause disease

parasite

a microorganism that survives by living in or on a host to which it causes harm

commensal

a microorganism receives benefits while the other microorganism gains neither benefit or harm

symbiont

an organism that gains mutual benefits with another microorganism in a symbiotic relationship.

heterotroph

Heterotrophs are organisms that cannot produce their own food and must consume other organic compounds for energy, including some bacteria, fungi, and parasites.

autotrophs

an organism that obtains energy through means other than organic compounds and often produce organic compounds such as oxygen

• photosynthesis - energy through absorption of light; bacteria and algae make up 70% of earth’s oxygen through photosynthesis

• chemosynthesis - energy obtained from inorganic compounds, often by bacteria in extreme environments.

decomposers

organisms that break down organic waste and matter and often recycles it back into the ecosystem

• fungi and bacteria

• important within the body as well as bacterial decomposers break down tissue into chemicals within the body. Also allows animals such as cattle to break down complex carbohydrates within their diet

prokaryotes

• include bacteria and archaea

• unicellular, lack a nucleus, very small (10x smaller than eukaryotes)

• found virtually everywhere (ubiquitous)

• reproduce asexually

Bacteria

prokaryotic (unicellular, lack nucleus, small)

• cell walls are made of peptidoglycan

• important in the process of making anti-biotics because they can produce substances that inhibit the growth of other bacteria.

• ex: E. coli, Staphylococcus, Streptococcus.

archaea

• prokaryotic (unicellular, no nucleus, small)

• often inhabit extreme environments

• cell walls are not made up of peptidoglycan

• example: halophiles, thermophiles.

Eukaryotes

• contain a nucleus

• larger than prokaryotes

• include fungi, protozoa, algae, and helminths

• can be unicellular or multicellular

• can reproduce sexually or asexually

Fungi

• eukaryotes (contain nucleus and organelles)

• often decomposers (heterotrophs)

• cell walls made of chitin (allows nutrients to be absorbed)

  • molds: reproduce via spores (multicellular) ; aspergillus

  • yeasts: reproduce via spore budding (unicellular) ; candida

what is the difference between yeasts and molds

Although yeasts and molds are both types of fungi, they function differently. Molds are multicellular and reproduce through the use of spores. An example of molds is Aspergillus. Yeasts, on the other hand, are multicellular and reproduce through spore budding, which is when a single cell develops into a new organism. An example of yeasts is Candida. (the cause of vaginal yeast infections)

protozoa

eukaryotic (have a nucleus and organelles)

• heterotrophs

• single celled

• reproduce sexually or asexually

• can be free living or parasitic

• motile

• can be found in water

• examples": amebomas, plasmodium, trichomonas

helminths

• eukaryotic

• multicellular

• parasitic worms

• include tapeworms and roundworms

viruses

• Acellular, meaning it has no cellular composition without a host cell and cannot reproduce independently.

• They consist of genetic material (DNA or RNA) surrounded by a protein coat and a lipid membrane

• contain infectious parasite particles

• teeny tiny

• examples: influenza, ebola, herpes

Viron: a virus particle outside of a host

prion

small proteins folded in intricate ways

contain no dna or rna so there is no genetic program and they can induce abnormal folding of normal proteins in the brain, leading to neurodegenerative diseases.

Prions are infectious agents composed solely of misfolded proteins, lacking nucleic acids, and they cause neurodegenerative diseases by inducing abnormal protein folding in the host's brain.

where is it normal to have microbacteria in the body and where should it not be

Normal microbacteria inhabit areas like the skin, mouth, gut, and respiratory tract, while they should not be present in sterile environments such as blood, internal organs (like the brain and heart), and the central nervous system.

four specific different beneficial functions of microorganisms

food production - through the use of fermentation, which is when microorganisms convert sugars into acids, gases, or alcohol, foods such as cheese, beer, and yogurt can be made.

Biotechnology/genetic engineering - bacteria can be used to produce needed things such as insulin by altering the DNA of bacteria to include human insulin-producing genes.

bioremediation - the use of microorganisms to clean up environmental pollutants, such as oil spills or heavy metal contamination. Bacteria such as the Bacillus species can degrade pollutants by breaking them down into less harmful substances.

decomposition - bacteria are vital in the body to help decompose human tissue into needed gases within the body, like carbon dioxide and nitrogen. They are also crucial within the environment to break down waste into nutrients that other organisms can reuse.

disproving spontaneous generation

Louis Pasteur - used the swan neck flask to ensure that broth stayed sterile proving that microorganisms come from existing life forms rather than emerging spontaneously.

• allowed other scientists to develop the germ theory

Antoni Van leewenhoek

began making and using simple microscopes and looked at microorganisms from his well water which he called animalcules at the time

carolus linnaeus

developed the taxonomy system (k,p,s,c,o,f,g,s)

robert koch

contributed to the germ theory

• first to link a particular germ to a particular disease

• staining techniques, first pic of microorganism, steam for sterilization, transferring techniques

• koch’s postulates

  • microorganism must be found in all diseased hosts and not in healthy organisms

  • must be isolated and grown outside of the host

  • must cause the disease when introduced to a healthy host

  • same agent must be found in the diseased experimental host

Christian gram

developed the Gram staining technique to classify bacteria into two groups based on their cell wall structure, which helps in identifying bacterial infections.

• peptidoglycan has a role in distinguishing between Gram-positive and Gram-negative bacteria by retaining or not retaining the crystal violet stain during the Gram staining process.

• gram positive = thick peptidoglycan layer, retains crystal violet stain

• gram negative = thin peptidoglycan layer, does not retain crystal violet stain

Ignaz Semmelweis

handwashing in maternity wards to reduce child bed fever

was highly rejected at the time due to prevailing medical beliefs, but later recognized as a crucial practice in infection control.

joseph lister

pioneered antiseptic surgery by introducing sterilization techniques to prevent infection during operations. He advocated for the use of carbolic acid to clean surgical instruments and the operating environment.

• reduced surgery mortality rate from 45% to 15% in just 4 years

Florence nightingale

Founder of modern nursing, known for her work in improving sanitary conditions in hospitals and her role in nursing during the Crimean War.

edward jenner

pioneered the smallpox vaccine, using material from cowpox lesions to induce immunity. His work laid the foundation for immunology and vaccination practices.

Luis Pasteur

French microbiologist known for developing the germ theory of disease and pasteurization, which kills harmful microorganisms in food and drink.