mcb2000 mod. 1

microbes/microogranisms include

bacteria, archaea, fungi, protozoa, algae, and viruses

viruses are obligate intracellular pathogens, what does that mean?

they need a host to grow and multiply themselves

microbes beneficial activities

generate oxygen by photosynthesis, produce chemical products, produce fermented foods, produce manufactured products and disease treaments

definition of microbiome

a group of microbes that live stably in/on the human body

the three domains of microorganisms are based on?

cellular organizations

the three domains of microorganisms are

Bacteria, Archaea, and Eukarya

what is in the Eukarya domain?

protozoa, fungi, and algae

what are the two types of cells?

prokaryotes and eukaryotes

what are prokaryotes?

a unicellular organism whose cells lack a membrane-bound nucleus and other membrane-bound organelles

what are eukaryotes?

cells that have a nucleus enclosed within the nuclear membrane and form large and complex organisms. can be unicellular or muticellular.

viruses are acellular structures, what does that mean?

it means viruses are not made of cells

protozoa, fungi, algae, animal, human, and plant cells are which type of cells?

eukaryotes

cyanobacteria is also known as

the oxygenic photosynthetic bacteria. they carry out photosynthesis, fix carbon dioxide and produce oxygen

What are key characteristics of Archaea?

Lack peptidoglycan, often extremophiles (halophiles, thermophiles), methanotrophs and methanogens.

methanotrophs

use methane as carbon source

methanogens

anaerobic (don’t require oxygen) and produce methane

what is mycology?

the study of fungi

what is mycosis?

fungal infection

fungi are chemoheterotrophs, what does that mean?

means they decompose complex organic matter

the two main forms of fungi

yeast and mold

is yeast a multi or unicellular organism?

unicellular

is mold a multi or unicellular organism?

multicellular

characteristics of protozoa

unicellular eukaryotes, inhabit water and soil, animal-like nutrition, complex life cycles, mostly waterborne, are either cysts or trophozoite

definition of cysts (protozoa)

dormant form of a protozoan that allows it to survive outside the host for transmission

definition fo trophozoite (protozoa)

active, vegetative, and pathogenic form that feeds, reproduces, and causes infection within the host

what is spontaneous generation?

that life arises from nonliving matter

what is biogenesis?

that living cells arise only from preexisting living cells

pasteur’s contributions to microbiology

showed microbes are responsible for fermentation, disproved spontaneous generation by proving microbes are present in the air (using swan-neck flask), developed pasteurization

what is fermentation?

the microbial conversion of sugar to alcohol in the absence of air

what is pasteurization?

the application of a high heat for a short time to kill harmful bacteria in beverages

who advocated for handwashing?

Ignaz Semmelweis

What is Koch’s postulates?

experimental steps that demonstrate that a specific microbe causes a specific disease

What did Alexander Fleming discover on accident?

the first antibiotic (penicillin)

what is immunology?

the study of immunity-vaccine development

what is microbial ecology?

the study of the relationship between microorganisms and their environment

what is biotechnology?

the use of microbes for practical applications (such as producing foods and chemicals)

what is microbial genetics?

the study of how microbes inherit traits

what is molecular biology?

the study of how DNA directs protein synthesis

what is genomics?

the study of an organism’s genes; has provided new tools for classifying microorganisms

what is recombinant DNA?

DNA made from two different sources- Gene therapy and genetically modified bacteria

what is gene therapy?

a medical approach that treats or prevents disease by altering a person's genetic material to correct genetic problems

what is genetically modified bacteria?

microorganisms that have been engineered to express specific traits or produce useful substances, such as medicines or enzymes, by altering their DNA.

characteristics of microbes

more diverse than plants and animals, more abundant than any other living thing, grows in every ecological niche that has a source of liquid water. has shaped the development of earth’s habitat, transform the geosphere, can affect the climate by production and use of CO2 N2 O2 and CH4, are ubiquitous, participate in many symbiotic relationships (work together) w/ other organisms, only a small fraction cause disease

some beneficial activities of microorganisms

sewage treatment (can recycle water), bioremediation (can clean up pollutants, composting municipal (household) wastes, insect pest control, recycling vital elements (such as carbon and nitrogen), converts carbon oxygen nitrogen sulfur and phosphorus into forms used by plants and animals

definition of normal microbiota

microbes normally present in and on the human body

what are some things the normal microbiota does for humans?

prevent growth of pathogens and produce growth factors such as vitamins B and K

what is resistance?

the ability of the body to ward off disease

some resistance factors include:

skin, stomach acid, antimicrobial chemicals

what are biofilms?

microbes attach to solid surfaces and grow into masses

Biofilms cause what and are often resistant to what?

cause infections and are often resistant to antibiotics

what was Lister’s contributions to microbiology?

proved microbes caused surgical wound infections. used phenol to treat such wounds

what is pathogenicity?

a microbe’s general ability to cause disease in a host

what is viurlence?

the severity of a pathogen

what does avirulent mean?

not able to cause disease

where is the DNA of prokaryotic cells located?

in their nucleoid

where is the DNA of eukaryotic cells located?

in their nucleus

how does fungi obtain nutrients?

by absorbing organic material from their environment

how does bacteria obtain nutrients?

they can use a wide range of chemical substances for their nutrition

how does protozoa obtain nourishment?

by absorption or ingestion through specialized structures

what are viruses consisted of?

a nucleic acid (DNA or RNA) surrounded by a protein coat

what is DNA?

a double-helix nucleic acid that stores an organisms genetic material for a long-term use. it contains deoxyribose. It’s bases are adenine (A), guanine (G), cytosine (C), and thymine (T). an organisms blue-print

what is RNA?

a single stranded nucleic acid that carries instructions from DNA to protein synthesis and other cellular functions. it contains ribose. It’s bases are adenine (A), guanine (G), cytosine (C), and uracil (U). copies and translates DNA for cell use!