Module 1 Flashcards
What is One Health?
A collaboration of multiple disciplines working to attain optimal health for animals, people and the environment.
Over the last decade, what accounts for 60% of infectious diseases?
Zoonotic diseases
What does Global health address?
Zoonotic disease control, outbreak preparedness, AMR and food safety and security.
What does food safety ensure?
Ensures that people have healthy, nutritious food free from contamination.
What is food sovereignty?
Empowering people to eat healthy food/make good dietary choices.
What is food security?
It ensures people have access to food that meets their dietary needs.
Bacteria and Archaea fall into what category?
Prokaryotes
Fungi, protozoa, protists and helminths fall into what category?
Eukaryotes
Viruses and Prions fall into what category?
Acellular (non-living)
What is a microbiome?
Aggregate of microorganisms in the human body.
What is bioremediation?
Introduction of microbes to restore stability to disturbed or polluted environments.
What converts nitrogen from the air into a usable form for plants?
Nitrogen fixers
True or False - Nitrogen is directly fixed by plants.
False. Nitrogen must be converted for plants to efficiently and safely use it.
What organisms are capable of fixing nitrogen?
Prokaryotes
In order from most toxic to least toxic, what are the steps in the Nitrogen cycle?
Ammonia (most toxic) to Nitrite to Nitrate (least toxic)
What is nitrification?
The process of converting ammonia to nitrite to nitrate. Occurs aerobically and carried out exclusively by prokaryotes.
Who were the first people to observe microbial life?
Robert Hooke and Anton Van Leeuwenhock
What is SEM?
Scanning Electron Microscopy
This type of microscopy scans the surface.
SEM
What type of microscopy requires the specimen to be coated in inert metal?
SEM
What is TEM?
Transmission Electron Microscopy
How does TEM work?
It transmits electrons through a thin section to show more internal features.
What type of microscopy shows more surface/shapes?
SEM
Who introduced Spontaneous Generation?
Aristotle
What is abiogenesis?
The origin evolution of life or living organisms from inorganic or non-living matter.
What is a protocell?
Self-organized endogenously ordered spherical collection of lipids and molecules.
What are the building blocks of life?
Amino acids
Who was the first to disprove spontaneous generation?
Redi
Explain how Redi disproved spontaneous generation.
He placed 3 pieces of meat in separate beakers, one with no top, one that was stoppered and another with gauze placed on top. Those that were open/partially opened grew microorganisms.
How did Spallazani disprove spontaneous generation?
He used nutrient-rich broth and boiled the flasks, immediately after boiling he stoppered one flask but not the other. The stoppered flask produced no bacterial growth while the open flask did. This proved microbes were present in the air.
Why didn’t Needham disprove spontaneous generation?
He left his flasks filled with nutrient-rich broth open to the air after boiling them and found that there was still microbial growth present.
Why didn’t the scientific community believe that Spallazani disproved spontaneous generation?
They believed it just meant that air was required for spontaneous generation.
Who was considered “The Father of Microbiology”?
Louis Pasteur
What theory did Pasteur propose?
The Germ theory of disease
What does the germ theory of disease state?
It states that many diseases are caused by microorganisms and that they invade humans, animals, and other living hosts. It states that their growth and reproduction within their hosts can cause disease.
What is pasteurization?
The process of destroying bacteria.
What is The Pasteur Effect?
Sugar fermentation
How did Chamberland accidentally discover the possibility of vaccines?
He left a culture growing over vacation and inoculated the chickens with an attenuated (aged) culture from which the chickens did not get sick. Even after injected them with a fresh culture they still did not get sick, indicating they had developed some form of immunity to the disease due to the attenuated inoculation.
Who was the first person to be inoculated against rabies and successfully treated for the infection?
Joseph Meister
Who is the founder of modern microbiology?
Robert Koch
Why was Koch’s work with anthrax so notable?
He was the first to link a specific microorganism with a specific disease, rejecting the idea of spontaneous generation and supporting the germ theory of disease.
What is Koch’s First postulate?
- Must be found in abundance in infected microorganisms but not healthy.
Why did Koch abandon his first postulate?
He discovered asymptomatic carriers of typhoid and cholera.
Why is Koch’s second postulate not considered accurate anymore?
There are certain microorganisms/entities that can not be grown in pure cultures, such as prions.
Why does Koch’s third postulate no longer stand?
Because not all organisms exposed to an infectious agent will acquire the infection and non-infection may be due to general health, proper immune function, or acquired or genetic immunity.
What are Koch’s Postulates supposed to be criteria for?
Four criteria that were established to identify the causative agent of a particular disease.
Who is the “Father of Antiseptic Surgery”?
Joseph Lister
Who is considered “The Father of Immunology”?
Edward Jenner
Who was the first to link diseases between animals and humans?
Rudolf Virchow
Who is considered “The Father of Modern Pathology”?
Virchow
Who coined the term zoonosis?
Virchow
Who is known as the founder of social medicine and veterinary pathology?
Virchow
Who discovered penicillin?
Alexander Fleming
What did Alexander Fleming discover with lysozymes?
He discovered lysozymes could kill bacteria.
Who classified bacteria into four groups based on shapes?
Ferdinand J. Cohn
What did Cohn show specifically with Bacillus?
He showed that Bacillus can change from a vegetative state to an endospore state when subjected to an environment harmful to the vegetative state.
Why is Edouard Chatton important?
He was the first to characterize prokaryotes and eukaryotes based on the presence/absence of a nucleus
Who is considered “The Father of Natural Immunity”?
Elie Metchnikoff
Who is responsible for the discovery of phagocytosis?
Metchnikoff
What is phagocytosis?
A defensive process in which the body’s WBC’s engulf and destroy microorganisms. (Cellular immunity)
Who is best known for their work with parasite life cycles?
Giovanni Battista Grassi
What is David Bruce known for?
Investigated Malta Fever and trypanosomes identifying the cause of sleeping sickness. He also described Chagas disease, known as American trypanosomiasis, is a tropical parasite dz caused by protozoan Trpanosoma cruzi, also spread by insects.
Who discovered viruses?
Dmitri Ivanowksy
What do all living things have in common?
Plasma membrane, ATP for energy, genetic information in DNA
What three things are present in all biological macromolecules?
Carbon, Hydrogen, Oxygen
What are the six major elements?
C, H, O, N, S, P
What is peptidoglycan?
Substance forming cell walls, responsible for turgor and cell shape to prevent lysis of bacteria.
What domain lack peptidoglycan?
Archaea
What are the three types of Archaea?
Methanogens, extreme halophiles and extreme thermophiles
What domain have peptidoglycan in the cell wall?
Eubacteria
What is Koch’s second postulate?
- Must be isolated from diseased organism
What is Koch’s third postulate?
- Cultured microorganisms should cause dz when introduced to healthy organism
What is Koch’s fourth postulate?
- The microorganism must be reisolated from the inoculated, diseased host and identified as being identical to original causative agent.
What are the 4 things genetic material must be able to do?
Contain information to construct life
Pass from parent to offspring
Be accurately copied
Account for known variation in and b/w species
What bacteria was Frederick Griffith working with?
S. pneumoniae
Briefly explain Griffith’s experiment.
He was inoculating different types of bacterial strains into mice to determine the effects on them- whether they died or lived depending on the bacteria type.
What was the conclusion of Griffith’s experiment?
Genetic material from the heat killed type-S bacteria had been transferred to the living type R bacteria.
What did Avery, MacLeod and McCarty prove?
That DNA is the genetic material
A nucleic acid is a polymer consisting of what three basic building blocks?
Phosphate, Sugar, Nitrogenous base
Describe the structure of DNA.
Double stranded helix, sugar phosphate backbone, bases on the inside, stabilized by hydrogen bonding
What are the three components of DNA?
Phosphate group
Pentose sugar (deoxyribose)
Nitrogenous base
What are the nitrogenous bases of DNA?
Purines (Adenine, Guanin)
Pyrimidines (Cytosine, Thymine)
What are the three components of RNA?
Phosphate group
Pentose sugar (Ribose)
Nitrogenous base
What are the nitrogenous bases of RNA?
Purines (Adenine, Guanine)
Pyrimidines (Cytosine, Uracil)
In what direction are sugar carbons numbered?
1’ to 5’
What carbon is the base attached to? What about the phosphate?
Base = 1
Phosphate = 5
What is a phosphodiester bond?
phosphate group that links 2 sugars
What forms the backbone of DNA?
sugars and phosphates
How many origins of replication do bacteria have? How many do eukaryotes have?
Bacteria - single origin
Eukaryotes- multiple origins
In what direction does synthesis of DNA begin?
5’ to 3’
The __________ strand is made in the direction the fork is moving- synthesized in one long _______ molecule. The ________ strand made as __________ __________ have to be connected later.
Leading, continuous, lagging, Okazaki fragments
Explain how DNA helicase works.
It binds to DNA and travels 5’ to 3’ using ATP to separate the strand and move the fork forwards.
Explain how DNA topoisomerase works.
It relieves additional coiling ahead of the replication fork.
What do single strand binding proteins do?
Keep parental strands open to act as templates.
DNA polymerase can only add nucleotide bases from what strand? What direction does synthesis continue?
Adds from a free 3’ end of the leading strand. Continuous in 5’ to 3’ direction
Process that produces an RNA copy or transcript of a gene
Transcription
Process of synthesizing specific polypeptide on a ribosome
Translation
What organisms have an additional intervening step of RNA processing where mRNA is processed into functionally active mRNA?
Eukaryotes
What do structural genes code for?
Polypeptides
What is tRNA and what does it do?
Transfer RNA- links mRNA and amino acid sequence in proteins (transports amino acids to the ribosome)
Where are RNA transcribed?
In the nucleus in eukaryotic cells
Where is rRNA transcribed?
Nucleolus
What are the three types of RNA?
mRNA, rRNA, tRNA
What is the main difference between prokaryotic and eukaryotic transcription?
In most prokaryotes a single RNA polymerase transcribes all RNA, but in eukaryotes, each step has more protein involved.
What does RNA polymerase II do?
Transcribes mRNA
What does RNA polymerase I and III do?
Transcribes nonstructural genes for rRNA and tRNA
What RNA polymerase requires 5 transcription factors in eukaryotic cells?
RNA polymerase II
What are the three stages of transcription?
Initiation, Elongation and Termination
What is it called when the immune system overreacts?
Cytokine Storm
If an immune response is non-specific, occurs immediately and is present from birth and always available it is what type of immune response?
Innate immune response
If an immune response is specific to the specific pathogens it is what?
Adaptive immune response
Immune memory is involved in what type of immune response?
Adaptive
A battery of responses to prevent entry and invasion
Innate response
What is the precursor for all immune cells?
Bone marrow
Where are stem cells found?
Bone marrow
List the myeloid cells (6 listed)
Eosinophils
Basophils
Mast cells
Monocytes
Dendritic cells
Macrophages
What are the lymphoid cells?
B cells, T cells, Natural Killer (NK) Cells
What is haematopoiesis?
Formation of the cellular components of blood
What are the primary lymphoid organs?
Thymus and bone marrow
What are the secondary lymphoid organs?
Lymph node, spleen, MALT (mucosa associated lymphoid tissue)
Where do T cells or T lymphocytes mature?
Thymus
Developing T cells are referred to as what?
Thymocytes
What lines of defense are innate and nonspecific?
First and Second
What lines of defense are adaptive and specific?
Third
What are the phagocytes of the innate immune system? What line of defense are they associated with?
Monocytes/macrophages
Eosinophils
Neutrophils
Associated with the second line of defense
What cells are involved in the innate immune system?
Macrophages
Eosinophils
Neutrophils
Dendritic cells
Macrophages
Basophils
Disorders in what immune system may cause chronic susceptibility to infection?
Innate immune system
What is the precursor to all immune cells?
Bone marrow
What 4 cells are granulocytes?
Neutrophils
Eosinophils
Basophils
Mast cells
What cells are agranulocytes?
Lymphocytes (T-cells, B-cells, NK cells)
Monocytes
What do monocytes mature into?
Macrophages in the tissue
What cells kill virus-infected and damaged cells?
Cytotoxic T-cells
What cells help cytotoxic T cells and B cells in their immune functions?
Helper T Cells
What cells produce antibodies?
B cells
What cells (members of dendritic cell family) reside in the epidermis and in the epithelia of respiratory, digestive and urogenital tracts?
Langerhans Cells
What phagocytic cells form the lining of sinusoids of the liver and are involved in the breakdown of RBCs?
Kupffer Cells
What are the 5 steps of phagocytosis?
- Chemotaxis
- Adherence
- Ingestion
- Digestion
- Elimination
What is the process by which a microbe is marked for destruction by phagocytes?
Opsonization
An antibody or other substance that binds to foreign microorganisms or cells, making them more susceptible to phagocytosis.
Opsonin
Inflammation, fever, and antimicrobial substances fall into what line of defense?
Second line
What are the 5 cardinal signs of inflammation?
Redness, pain, heat, swelling, loss of function
What are 2 effects of inflammation?
Destroy or limit infection
Repair the damaged tissue
What controls body temperature?
Hypothalamus
During infection, products of microbes induce the release of what?
Cytokines
True or False
Elevated body temperatures decrease the effectiveness of the immune cells
False- it is thought that elevated body temps can help certain immune cells be MORE effective
Is Complement part of the innate or adaptive immune system?
Innate Immune system
What are the 3 complement pathways?
- Classical pathway
- Alternate pathway
- Lectin pathway
What initiates the classical pathway?
Antigen antibody complexes
What initiates the alternate pathway?
Interaction between C3, factors B,D,P and the pathogen
What initiates the lectin pathway?
Microbial carbohydrate components (PAMPs) and mediated by MBP
Activation of C3 is required for what pathways?
Classical and Alternative complement pathways
What coats the microbes and enhances phagocytosis?
Opsonins
What induce the release of histamine and result in severe allergic reactions?
Anaphylatoxins
Membrane Attack Complex happens during polymerization of what complements?
C5-C9
When does initiation of MAC occur?
C5-C7
Binding of what allow insertion into the lipid bilayer membrane?
C6 binding to C7
Interferons are released by host cells in response to what?
Infection with pathogens (ie. viruses)
What are the 3 main types of interferons?
Alpha, Beta, Gamma
Alpha and beta are what type interferon?
Type 1
Gama is what type interferon?
Type 2
What is the function of siderophores in bacteria?
To sequester iron from the body
True or False
Iron is required for bacterial growth
True
Aspect of immunity that is mediated by macromolecules present in extracellular fluids
Humoral response of immunity
Specific piece of an antigen that an antibody binds to
Epitope
Any substance that causes the immune system to produce antibodies
Antigen
True or False
Hapten is an incomplete antigen
True
What attaches to a carrier molecule to induce an antibody response?
Hapten
Antibodies are proteins called?
Immunoglobulins (Ig)
True or false
One antibody molecule has one antigen binding site
False
One antibody molecule has 2 identical antigen binding sites
What does valence refer to?
The number of antigen binding sites in an antibody
What can the Fc region bind to?
Complement, or cell such as a macrophage or phagocyte
True or False
Plasma cells produce small quantities of antibodies against a particular antigen.
False
Plasma cells produce LARGE quantities of antibodies against a particular antigen
True or False
Some B cells differentiate into long lived memory cells
True
Secondary immune response occurs as a result of memory, also known as?
Anamnestic response
What antibody is found in the largest quantity?
IgG
What antibody does placental transfer?
IgG
What is the first antibody produced in response to infections?
IgM
What antibody functions in allergic reactions?
IgE
What MHC is present in all nucleated cells?
Class I MHC
What are the class II MHC?
Macrophages, B cells and dendritic cells
What MHC is present only on antigen-presenting cells?
Class II MHC
What are the membrane associated glycoproteins that play a major role in cell-mediated immune responses by binding to foreign antigens and presenting them to T-cells?
Major Histocompatability Complex (MHC)
What are the antigen presenting cells?
Macrophages (monocytes when in blood), B cells, Dendritic cells
CD4 T cells are also known as?
Helper T cells
CD8 T cells are also known as?
Cytotoxic T Cells
What are the chemical messengers that aid in cell to cell communication?
Cytokines
What are the small cytokines that are involved in chemotaxis?
Chemokines
MHC class that has the highest gene density but some of the genes are not involved in the immune system
Class III MHC
What is the result of ADCC?
Kills the target cells by initiating apoptosis.
True or False
APC’s are cells that process and present antigens for B cell recognition?
False
APC’s are cells that process and present antigens for T cell recognition
The host to host transfer of genetic material, horizontal gene transfer, is seen it what molecules?
Plasmids
A small, circular, double stranded DNA molecule, distinct from a cell’s chromosomal DNA, and can replicate independently.
Plasmid
The genes carried in ________ provide bacteria with genetic advantages (such as antibiotic resistance)
Plasmids
Naturally exist in bacteria cells but also occur in some archaea and eukaryotes.
Plasmids
A major double membrane organelle found in the cells of plants and algae
Plastids
The site of manufacture and storage of important chemical compounds used by the cell (in plants), often used as drug targets for chemotherapy
Plastids
Derived non-photosynthetic plastid
Apicoplast
Originates from an alga through secondary endosymbiosis
Apicoplast
Lab technique used for detection of specific DNA sequence
Southern Blotting
Technique used in molecular biology research to study gene expression by detection of RNA
Northern Blotting (RNA Hydridization)
Technique used in molecular biology to identify specific proteins from a complex mixture of proteins.
Western Blotting
Who invented PCR?
Kary Mullis
Process in which specific DNA fragments are amplified from genomic DNA
PCR
What are the components of PCR?
Template DNA
Oligonucleotide primers
DNTP
Taq polymerase
What is the order of actions in a PCR?
- Denaturation
- Annealing
- Elongation
What kind of growth do we see in PCR?
Exponential
Real time PCR is quantitative of or qualitative?
Quantitative
Laboratory technique based on PCR that monitors amplification of a targeted DNA molecule. No gel is used.
Real time PCR
What is the key difference between dPCR and traditional PCR?
The method of measuring nucleic acid amounts.
In digital PCR, a single reaction is carried out but the sample is separated into large number of partitions and the reaction is carried out in each individually.
Quantification is used in what type of PCR?
Digital PCR
This type of PCR is used to detect RNA expression and can be a one step process or a two step process.
RT PCR (Reverse Transcription)
What RT PCR is useful for detecting multiple messages from a single RNA sample?
Two-step RT PCR
What PCR allows for greater flexibility when choosing primers and polymerase?
Two step RT PCR
