PCOL 465 Exam 1

What is the alternative when a cell wall is hard to gram stain in bacteria?

Acid fast staining -- Acid fast bacteria appear gram positive on a gram stain.

Explain Louis Pasteur's experiment.

Boiled meat broth in flasks with S necks to explain that spoilage of liquid was caused by particles in the air rather than the air its self. - important pieced of evidence supporting the germ theory of disease.

The genomes of most ____ viruses are transcribed by the host ____-dependent ____ ______.

DNA, DNA, RNA polymerase

The genomes of viruses can be either __ or __, but not both.

DNA, RNA

Virus can either be surrounded by an ____ or "naked" and only have a ____.

Envelope, capsid

Importance of Carolus Linnaeus?

Established the system of scientific nomenclature. - created taxonomy

In the process of translation, prokaryotes and eukaryotes used different ribosomes. Which uses what?

Euk: 80S ribosome made up of 60S & 40s subunits Pro: 70s Ribosome made up of 50S and 30S subunits

Are plasmids essential for bacterial survival?

NO, but they provide bacteria with resistance to antibiotics which help them survive.

List the major classes of microorganisms in terms of ascending/increasing size:

Smallest: viruses, bacteria, fungi, and parasites: Largestest

Do Vaccines stimulate the innate or adaptive immunity?

adaptive

Phenotype refers to ____ or characteristics resulting from integration if genotype and environment.

appearance

Most bacteria are gram-___, but clinically important bacteria are often gram-___.

negative, positive

What does the microbial classification anaerobe mean?

not does require O2 = fermentation

Viruses are referred as ___ ____ parasites.

obligate intracellular parasites. ** know that there are plant, animal, and bacterial viruses.

Photosynthetic algae (oceanic algae) contribute to the atmosphere by producing ____ through ____.

oxygen, photosynthesis *** 50% of all the oxygen

Alexander Fleming (1928) discovered __.

penicillin

Gram-negative vs Gram-positive bacteria is all about the thickness of the ____ cell wall.

peptidoglycan

Fungi are ___ like microorganisms that do not have a _____. Therefore, they are not green. Fungi can be unicellular such as ____ or multicellular organisms such as ___. The are mostly found in ____ and ____ places.

plant chlorophyll yeasts molds warm moist

What are plankton? and are they microbes?

they are microorganisms that live in the water that can not move on their own. They DO NOT cause disease or ferment, therefore are not microbes.

What is the primary function of LPS (lipopolysaccharide)?

to provide structural integrity and a permeability barrier to protect the bacterial cell from entry on hazardous molecules.

Plus-sense single stranded RNA viruses are able to ____ first because they are similar to mRNA.

translate - they go straight to the ribosome to replicate

What does the microbial classification microaerophilic

"little O2" survives in conditions in which O2 is reduced (8%-10% vs ~21%).

What is the second line of defense within the immune system?

- adaptive immunity: cell mediated & humoral (antibody dependent)

What does the microbial classification aerobes mean?

microbe that requires O2, respiration

What is a prion?

misfolded protein that causes disease ex: mad cow disease

Explain the life cycle of Schistosoma mansoni

- an infected human host excretes eggs in feces - in freshwater the eggs hatch - the hatch larvae infect an intermediate snail host. Where the parasite matures and then releases back into the water - the parasite (cercariae) can now infect a human host via penetration of the skin - injected human releases eggs via bowels from mature female worms to complete the worms life cycle.

Importance of Jon Snow.

- did not believe miasma - determined fecal-oral transmission of cholera. - First to recommend water to be boiled and filtered. - determined the London cholera outbreak 1854 came from a water pump = beginnings of epidemiology.

Briefly describe the life cycle of the malaria parasite:

- involves two host - mosquito --> to human via blood

Explain the miasma theory of disease/germ theory.

- miasma was considered to be poisonous vapor that was identifiable by smell . This theory believed that disease was not spread through individuals but rather infected individuals would give rise to the infection vapors. - stated diseases were a product of contaminated water, foul air, and poor hygiene.

What are the 5 steps of the viral replication cycle?

1) Attachment, 2) penetration/entry via direct fusion, 3) Replication/synthetic phase (transcription, translation, and replication) 4) assembly 5) release

List the three broad effector pathways for the complement system:

1) Lysis -> insert holes in membrane 2) inflammation -> cytokines 3) opsonization/phagocytosis -> mark for death

List Koch's postulates

1) The microorganism must be found in abundance in all organisms with the disease but should not be found in health organisms 2) The microorganism must be isolated from the diseased organism and grown in pure culture. 3) The cultured microorganism should cause disease when introduced into a healthy organism. 4) The microorganism must be re-isolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent. ** understand that there exceptions to this: prions, viruses, malaria, hence there is a new "modern version of the postulates

List the 4 way viral infection usually ends:

1) cell death - nearly all infected cells die 2) budding - most human enveloped viruses acquire their membrane by budding through the plasma/nuclear membrane 3) cell survival - for retroviruses (expect HIV-1 & lentiviruses) 4) the latent state - Viral DNA can be either extrachromosomal (herpes) or become integrated into the chromosome (retrovirus).

Describe the two ways in which DNA viruses replicate when in a host cell:

1) dependent on host machinery to replicate its DNA in the nucleus (ex: herpesvirus) 2) Independent of cellular functions. Replicate in the cytoplasm. Must code for almost all of the enzymes and proteins required for replication. (ex small pox).

List the 10 things microbes do for us that are good:

1) digestion 2) immune system development 3) Vitamin K production 4) Food production (nitrogen fixation, bread, cheese, yogurt..) 5) molecular biology 6) medicine production 7)vaccine production 8) sewage treatment 9) the air we breath 10) antibiotics

What are the 5 steps of infection:

1) exposure, adherence, evasion of the immune system 2) Colonization and proliferation (replication) 3) invasion 4) tissue damage 5) Dissemination with host or spread to others.

What are the three evens that changed life expectancy?

1) public health & sanitization 2) antibiotics 3) vaccines

In prokaryotic DNA replication there is/are ___ origin of replication and __ replication fork/s.

1, 2

How many chromosomes do humans have?

23 pairs, 46 total

How many different types of plasmids are there? - Which one is most important for encoding antibiotic resistance?

3, R factors

The human body consist of about ___ trillion human cells, with an additional ___ trillion microbes in and on the body.

30, 39 * it's fairly equal

What direction DNA replicated and transcribed?

5' to 3' ALWAYS

There are ____ microbes on the planet. There are 'only' an estimated ____ species.

5x10^30 1x10^12 (1 trillion)

Protozoa are single celled ___ with animal like behaviors such as hunting, motility, no cell wall: - List 4 of the protozoan microbes talked about in class:

Eukaryotes - Amoeba: change shape using pseudopods - Flagellates: move by flagella - Ciliates: move by hair-like projections - Apicomplexans: intracellular parasites that use apicoplast to enter host cells.

How do the cell walls of eukaryotes differ from prokaryotes?

Euks are made up of chitin and cellulose (in yeast), while bacteria cell walls are composed of peptidoglycan. **human cells do not have cell walls only euk plant cells

What method is used to differentiate gram-positive vs gram negative bacteria? - how do they defer using this method?

Gram staining - gram + = purple - gram - = red/pink

____ are parasitic worms that include tape worms, flukes, and round worms. * only microbe that can be ___.

Helminths seen with naked eye.

____ are also associated with bacterial gene transfer and are very quick using assembly platforms.

Integrons

What are microorganisms and how do they differ from microbes?

Microorganisms are minute living things that usually unable to be viewed from the naked eye. Microbes are a subclass of microorganisms that play roles in disease or fermentation.

Explain how there is cross communication between the innate and adaptive immune systems.

Phagocytes (innate) have receptors on their surface that recognize PAMPs (pathogen associated molecular patterns) such as: LPS and other endotoxin, flagellin, peptidoglycan, "abnormal" nucleic acids. These trigger binding and phagocytosis. Microbes are then digested and resulting antigen are presented to the adaptive immunity.

Give an example of an organism that can be both plant an animal at the same time:

Phytoplankton

Besides chromosomes, where else can DNA be found?

mitochondria, chloroplasts, & plasmids

__ & ___ cells that are apart of the adaptive immune system are highly specific for each ____ and enhanced by repeated ___ to the same ____.

T, B, antigen, exposure, antigen

True or False: Prokaryotes do not have introns or poly A tails.

TRUE

True or false: Some microbes are pathogenic while many are beneficial.

TRUE

What is transcription? - What are it's 3 stages

The process of copying DNA to RNA - initiation, elongation, and termination

What is the study of microbiology?

The study of microorganisms

How many cells are in the human body? How does this compare to the amount of microbes on/in the body?

There are about 30 trillion cells within the human body and about 39 trillion microbes on/in the body. _ The numbers are fairly equal - in terms of mass, microbes don't even compare

Minus-Sense RNA Viruses have to _____ first in order start the replication process.

Transcribe - it has to transcribe to mRNA before translation can occur.

List the three bacterial sexual processes of gene transfer:

Transformation: naked DNA is taken up from the environment by bacterial cells. Transduction: use of bacteriophages to transfer DNA between cells. Conjugation: direct transfer of DNA from one bacterial cell to another. ** also be aware of lysogenic conversion - uses phages

____ are discrete DNA segments that are able to move themselves (& associated resistance genes) almost randomly to new locations in the same or different DNA molecules with in a cell. Also known as "jumping genes".

Transposons

Are more microbes good or bad?

Trick question: we don't know.

What are the 5 major classes microorganisms?

bacteria, fungi, protozoa, algae, and viruses

Microbes are mainly include ___, ____, & are _____. Either cause ___ or undergo ____.

bacteria, prokaryotes, unicellular.

Why are there fewer antifungal and antiprotozoal drugs when compared to antibiotics?

because they are Euks and have similar metabolic and structural similarities to human cells (host).

What is one of the reasons to study microbes?

because they are a result of the leading causes of death globally * 3 in the top 10 causes of death

What does the microbial classification facultative mean?

can survive with or without O2 = respiration & fermentation.

The genus is ____, while the epithet is ____.

capitalized, lower case - are either italicized or underlined ex: Escherichia coli

Fungi have a rigid ____ ____, obtain energy and nutrients from environment (hosts). Fungi cause ____.

cell wall, mycosis

Bacteria have a ____ ___, but with a cell plan called "____" that lacks organelles of ____ cells.

cell walls, "prokaryotic", eukaryotic

Viruses are not ___ at all. They have a ___ and some structural elements, but must take over the machinery of another living cell (eukaryotic or prokaryotic) to ____.

cells, genome, replicate

fimbriae and pili are extensions of the ____ membrane and are made up of an oligomeric protein known as ____.

cytoplasmic, pilin

Gram-____ have an outer membrane composed of _____, which is highly antigenic.

negative, lipopolysaccharides (LPS) ** LPS stick out of the capsule

Bacteria Metabolism used ____ and ___ transport for substrate sources. ATP generation used _____ and or _____.

diffusion, active, fermentation, respiration

Fungi are ____, but have a rigid external ____ that makes them more like ____ than ___.

eukaryotic, wall, plants, animals

Each organism has two names: the __ and specific ____.

genus, epithet

List 4 different species of eukaryotes:

humans, protozoa, fungi, and helminths

Why did life expectancy increase around the earlish 1900's?

hygiene increased

RNA virus replication takes place where?

in cytoplasm * therefore, these viruses need to encode for their own transciptases and polymerases/replicases.

Which part of the immune system is considered 1st line of defense? what does this include?

innate immunity: skin, saliva, pH, phagocytosis, and complement system.

An essential step in every virus infection is the production of virus-specific ____ that program the cellular ribosomes to synthesize viral proteins.

mRNAs

Importance of Anton Van Leeuwenkoek?

made the first microscope - first person to actually see living microorganisms.

Algae are ___ like microorganisms. They can exist as _____ or ___-____ organisms. They contain _____. Due to the presence of ____ they can photosynthesize. Some algae have color pigments like ____ and ___. Therefore, bases on the color of the pigment present they can be classified into different categories such as ____ algae, ___ algae, and ____-____ algae.

plant unicellular multi-cellular chlorophyll chlorophyll blue green green blue blue-green

A capsule is made of ____ "slime'" layer protecting mostly gram-___ bacteria.

polysaccaride, negative ** but can be found on gram+

The ____ strand ___ viruses, such as coronaviruses and the herpesviruses possess genomes that can be used directly as mRNAs that are translated immediately on entry into the cytoplasm of the cell.

positive(+), RNA

The cell walls of gram-___ have a ____ layer of peptidoglycan, while the cell walls of gram-___ bacteria are _____, but is covered by a ___.

positive, THICK, negative, thin, capsule

Parasite refers to microorganisms that are physiologically dependent upon their host for survival and belong to the major taxonomic groupings ____, _____, and _____.

protozoa, helminths, fungi * also viruses are considered parasites

Microorganisms are responsible for much of the breakdown of and natural ___ of ___ material in the environment. Some synthesize ____ containing compounds that contribute to the nutrition of living things that lack this ability.

recycling, organic, nitrogen

The ___ (HIV, HTLV-1,2) are a special class of ___ strand mRNA viruses that need DNA by reverse transcription.

retroviruses, positive - they go from + --> - stranded then to DNA

What is the big exception to the central dogma?

reverse transcription carried out by reverse transcriptase --> RNA-dependent DNA polymerase. ** but there are many other exceptions to this theory (see photo)

DNA or RNA genomes maybe ___ or ____ stranded. ____ genomes can either be __ sense, ____ sense, ____ ambisense.

single, double, RNA, positive, negative, both +/-

Parasites exists as ____ or ____ structures with the same compartmentalized ____ cell plan of our own cells. Which includes a ____ and ____ organelles like mitochondria.

single, multicellular, eukaryotic, nucleus, cytoplasmic

Viruses are one of the ___ microorganisms. They are so small that they can not be seen even through an ordinary compound ____. The name virus is derived from a Latin word meaning "____". To observe virus's special microscopes called ___ microscopes are used.

smallest microscope poison electron

Bacteria are the ___ and oldest known unicellular organisms on Earth. Bacteria are mostly present as single celled microorganisms, but sometimes live in groups called ____. They can be found almost everywhere such as air, water, and even ___. Some bacteria are useful while some are ____. Harmful bacteria enter the body through ___ or ___ cause diseases like _____ and ____.

smallest, colonies soil harmful air/water. cholera typhoid

Protozoa are ___ microorganisms that have ____ like characteristics. They can move from one place to another and can hunt their food. They are mostly ____ but can also be found in the ___ and the bodies of other organisms. Such protozoa that live in the bodies of other organisms are called _____.

unicellular animal aquatic soil parasites

Pili (fimbriae) are crucial ___ factors for many Gram-____ pathogens. These surface structures provide bacteria with a link to their external environments via attachment.

virulence, negative

Which cells type is involved in phagocytosis?

while blood cells - neutrophils, monocytes, macrophages, mast cells, and dendritic cells)

What are the 4 medically important fungi:

yeast: candida albicans/auris Molds: black mold Fungi: athlete's foot, jock itch, ringworm Dimorphic: valley fever