Microbiology Chapter 15- Mastering Micro 2016

Which of these statements is true regarding portals of exit? 1. In most cases, a microbe uses the same portal for both entry and exit. 2. The urinary tract is the most common portal of exit. 3. The portal of exit for chicken pox, measles, and smallpox is the skin. 4. Polioviruses most often use the respiratory portal of exit.

In most cases, a microbe uses the same portal for both entry and exit

The mechanism by which gram-negative bacteria can cross the blood-brain barrier

Inducing TNF

-Epidermis tightly packed cells with keratin -Keratin ( protective protein) -Shedding, low moisture

Intact skin

Radio operator btw Leukocytes

Interleukins

cell that displays foreign antigens complexed with major histocompatibility complexes (MHCs) on their surfaces

(antigen) presenting cell

Which of these events leads to all of the others in a pyrogenic (fever) response? 1. Endotoxin is released from the cell wall of gram-negative bacteria. 2. The hypothalamus releases prostaglandins. 3. IL-1 is released by macrophages. 4. The body's thermostat is set to a higher level, and fever occurs. 5. IL-1 travels via the blood to the hypothalamus.

1. Endotoxin is released from the cell wall of gram-negative bacteria.

Which statement is not true of endotoxins? 1. They are eliminated from the body as a result of antitoxin production. 2. They are more heat-resistant than exotoxins are. 3. They can lyse amoebocytes found in crab hemolymph. 4. They can induce chills, fever, aches, clotting, shock, and miscarriage. 5. Endotoxins are produced by Neisseria meningitidis and E. coli.

1. They are eliminated from the body as a result of antitoxin production.

Which disease is correctly matched with the common portal of entry? 1. poliomyelitis; mucous membranes of gastrointestinal tract 2. chlamydia; skin 3. influenza; mucous membranes of genitourinary tract 4. measles; parenteral route 5. hookworm; mucous membranes of genitourinary tract

1. poliomyelitis; mucous membranes of gastrointestinal tract

how many antigen binding sites do most human antibodies have

2

Viruses can evade host defenses by ________. 1. producing enzymes that destroy antibody molecules 2. "hiding" inside host cells where they cannot be detected by the host's immune system 3. producing leukocidins that actively destroy white blood cells 4. inhibiting phagocytosis due to the presence of the viral envelope

2. "hiding" inside host cells where they cannot be detected by the host's immune system

Which of these effects is most likely to occur if a pathogen enters the body by a portal of entry other than the preferred one? 1. A more severe disease will result. 2. A milder disease will result. 3. A different disease of the same severity will result. 4. Pathogens cannot enter by alternate routes.

2. A milder disease will result

The pathogenicity of which of the following is not the result of lysogeny? 1. Clostridium botulinum 2. Clostridium tetani 3. Vibrio cholerae 4. Streptococcus pyogenes 5. Corynebacterium diphtheriae

2. Clostridium tetani

Which of these substances are most important in the establishment of biofilms? 1. exotoxins 2. adhesins 3. siderophores 4. hemolysins 5. invasins

2. adhesins

Which one of these pairs is not correctly matched? 1. collagenase; breaks down connective tissue 2. coagulase; lyses fibrin clots 3. leukocidin; lyses WBC membranes 4. siderophore; traps iron 5. IgA protease; digest antibodies

2. coagulase; lyses fibrin clots

Which of these statements is not true for bacterial capsules? 1. For Streptococcus pneumoniae, the encapsulated strain is more virulent. 2. Pathogenic and nonpathogenic bacteria can produce capsules. 3. Antibodies produced against a capsule cannot affect whether disease will occur. 4. The importance of the capsule to virulence for Streptococcus pneumoniae can be determined because there are strains both with and without the capsule. 5. Capsules related to virulence are produced by the causative agents of anthrax and bubonic plague.

3. Antibodies produced against a capsule cannot affect whether disease will occur.

The LD50 of Vibrio choleraeis 108 cells through the oral route. If the bacterial cells are ingested with bicarbonate, the LD50 drops to 104. Which of these explanations is the most likely? 1. Vibrio cholerae makes toxin only in the presence of stomach acid. 2. Stomach acid increases the virulence of Vibrio cholerae. 3. Stomach acid decreases the virulence of Vibrio cholerae. 4. Sodium bicarbonate inactivates Vibrio cholerae. 5. Sodium bicarbonate decreases the virulence of Vibrio cholerae.

3. Stomach acid decreases the virulence of Vibrio cholerae.

All of these answers are true of A-B exotoxins except ________. 1. Many exotoxins are A-B toxins. 2. They consist of two polypeptide components. 3. They are produced only by gram-negative bacteria. 4. The A portion of the toxin is the active component. 5. The B portion of the toxin binds to surface receptors on host cells.

3. They are produced only by gram-negative bacteria.

The ID50 for cutaneous anthrax due to Bacillus anthracis is 10-50 endospores, while the ID50 for inhalation anthrax is 10,000 to 20,000 endospores. This means that ________. 1. not enough information is available to answer this question 2. neither cutaneous or inhalation anthrax can easily be acquired. 3. cutaneous anthrax is easier to acquire than inhalation anthrax 4. inhalation anthrax is easier to acquire than cutaneous anthrax 5. both cutaneous and inhalation anthrax can easily be acquired

3. cutaneous anthrax is easier to acquire than inhalation anthrax

Which of these conditions would not affect the ability of Streptococcus mutans to attach to teeth? 1. the lack of a glycocalyx 2. the lack of the enzyme glucosyltransferase 3. the absence of Actinomyces, a bacterium that can be part of dental plaque 4. the inability to form dextran 5. the lack of sucrose

3. the absence of Actinomyces, a bacterium that can be part of dental plaque

All of the following are examples of cytopathic effects of viruses except ________. 1. cell surface antigens change 2. host cells fuse to form multinucleated syncytia 3. inclusion bodies are found in the cytoplasm or nucleus 4. None of these choices. There are no exceptions here.

4. None of these choices. There are no exceptions here.

Which of these viral cytopathic effects is most likely to be associated with the development of cancer? 1. cell fusion 2. stimulation of interferon production 3. inclusion bodies 4. loss of contact inhibition 5. cell death

4. loss of contact inhibition

how many classes of antibodies are there

5

Capsules play a role in the virulence of all of the following except ________. 1. Bacillus anthracis 2. Klebsiella pneumoniae 3. Yersinia pestis 4. Haemophilus influenzae 5. Mycobacterium tuberculosis

5. Mycobacterium tuberculosis

Which statement is true of endotoxins? 1. They are disease specific. 2. They are produced by gram-positive bacteria. 3. They are proteins. 4. They increase blood pressure. 5. They are released upon cell lysis.

5. They are released upon cell lysis.

Which of these eukaryotic molecules/structures can be responsible for movement of bacteria within host cells? 1. invasins 2. cilia 3. flagella 4. pseudopods 5. actin molecules

5. actin molecules

In response to the presence of endotoxin, phagocytes secrete tumor necrosis factor. This causes

A decrease in blood pressure

A newly identified bacterial pathogen has been shown to cause disease in humans, disrupting the production of some proteins by interfering with the function of the endoplasmic reticulum of liver cells. Under specific growth conditions, this bacterial strain secretes a protein that appears to be responsible for the pathology of the disease. This protein is composed of two polypeptide chains, one of which binds to a receptor on the surface of liver cells, stimulating the uptake of the protein by endocytosis. Once inside the cell, the other polypeptide component interferes with the activity of ribosomes bound to the endoplasmic reticulum. This bacterial protein will most likely be classified as a/an ________.

A-B toxin

Which of the following cytopathic effects is cytocidal? A. Release of enzymes from lysosomes B. Inclusion bodies C. Antigenic changes D. Giant cells E. Transformation

A. Release of enzymes from lysosomes

_______ are molecules on bacterial cell surfaces that enable them to adhere to the surface of host cells.

Adhesins

- Antibodies cause antigens to clump together - IgM used for cross linking - making it easier for phags to eat

Agglutination

The symptoms of tetanus are due to

An exotoxin produced by clostridium tetani

- Antibodies attached to target cell -Causes destruction by MACROPHAGES AND NK CELLS

Antibody-depended cell-mediated cytotoxicity

____ remain in red bone marrow

B cells

_____ are the bases of humoral immunity

B cells

________ are directed at antigens in blood or bodily fluids

B cells

Which organism most easily causes an infection? A. Treponema pallidum ID50-57 B. Legionella pneumophila ID50-1 C. E. coli O157:H7 ID50-20 D. Shigella ID50-10 E. Can't tell

B. Legionella pneumophila ID50-1

Endotoxins are A. Specific in their method of action. B. Part of the gram-negative cell wall. C. Associated with gram-positive bacteria. D. Excreted from the cell. E. None of the above.

B. Part of the gram-negative cell wall.

Which of the following statements about exotoxins is generally not true? A. They are more potent than endotoxins. B. They are not inactivated by heat. C. They are composed of proteins. D. They are produced by gram-positive bacteria. E. They have specific methods of action.

B. They are not inactivated by heat

Cytopathic effects are changes in host cells due to A. Bacterial infections. B. Viral infections. C. Protozoan and helminthic infections. D. Fungal infections. E. All of the above.

B. Viral infections.

-Least common WBC -Produce histamine , important Inflamm response

Basophil

Botulism is caused by an exotoxin, therefore it could easily be prevented by _________

Boiling food prior to consumption

All of the following may be used for adherence except A. Glycoproteins. B. Lipoproteins. C. Cell membrane mannose. D. Fimbriae. E. Capsules.

C. Cell membrane mannose.

Thirty-two people in San Francisco who ate jackfish caught at Midway Island developed malaise, nausea, blurred vision, breathing difficulty, and numbness from 3 to 6 hours after eating. The most likely cause of this food intoxication is A. Staphylococcal enterotoxin. B. Cholera toxin. C. Ciguatera. D. Aflatoxin. E. A mycotoxin.

C. Ciguatera.

Which of the following organisms doesn't produce an exotoxin? A. Staphylococcus aureus B. Clostridium tetani C. Salmonella typhi D. Corynebacterium diphtheriae E. Clostridium botulinum

C. Salmonella typhi

-Fungistatic fatty acid in sebum (oil secretion from skin) -Lysozyme in perspiration (tears , saliva and urine) -low ph in gastric juice and vaginal secretions -high salt content of sweat all examples of ?

Chemical factors

Which of these organisms does not produce an enterotoxin? 1. Shigella spp. 2. Clostridium botulinum 3. Vibrio cholerae 4. Staphylococcus aureus

Colostridium botulinum

Given the following LD50 values for Bacillus anthracis, through which portal of entry is it easiest to get anthrax? 1. All are equally easy portals of entry. 2. Cutaneous-50 endospores 3. Inhalation-20,000 endospores 4. Ingestion-1,000,000 endospores

Cutaneous 50 endospores

Allows communications btw different cells in immune response

Cytokines

Radio operator for the Immune army

Cytokines

Symptoms of protozoan and helminthic disease are due to A. Waste products excreted by the parasite. B. Products released from damaged tissues. C. Tissue damage due to growth of the parasite on the tissues. D. All of the above. E. None of the above.

D. All of the above.

Which of the following is not true of staphylococcal enterotoxin? A. It is an exotoxin. B. It causes diarrhea. C. It causes vomiting. D. It is produced by Staphylococcus aureus growing in the host's intestines. E. None of the above.

D. It is produced by Staphylococcus aureus growing in the host's intestines.

All of the following are methods of avoiding host antibodies except A. IgA protease. B. Invasims. C. Antigenic change. D. Membrane-disrupting toxins. E. None of the above

D. Membrane-disrupting toxins.

Septic shock due to gram-positive bacteria is caused by A. Membrane-disrupting toxins. B. A-B toxins. C. Lipid A. D. Superantigens. E. All of the above.

D. Superantigens.

Which of the following statements is false? A. Hyaluronidase breaks down substances between cells. B. Hemolysins lyse red blood cells. C. Kinase destroys fibrin clots. D. Leukocidins destroy neutrophils. E. Coagulase destroys blood clots.

E. Coagulase destroys blood clots.

Which of the following does not contribute to a pathogen's invasiveness? A. Capsule B. Hyaluronidase C. Cell wall D. Ligands E. Exotoxins

E. Exotoxins

All of the following are true about M protein except A. It is heat- and acid-resistant. B. It is a protein. C. It is found on fimbriae. D. It is found on Streptococcus pyogenes. E. It is readily digested by phagocytes.

E. It is readily digested by phagocytes.

Which of the following is not a cytopathic effect of viruses A. Cell death B. Increased cell growth C. Inclusion bodies form in the cytoplasm or nucleus D. Host cells fuse to form multinucleated syncytia E. None of the above

E. None of the above

A cell wall can increase a bacterium's virulence because cell wall lipid A A. All bacteria have a cell wall and all are not pathogenic; therefore, cell walls do not contribute to virulence. B. Helps the bacterium attach. C. Resists phagocytosis. D. Destroys host tissues. E. None of the above.

E. None of the above.

Which of the following organisms causes the most severe disease? A. Shigella disenteria ID50-10 B. Treponema pallidum ID50-57 C. Salmonella enteriditis ID50-20 D. Parainfluenza virus ID50-200 E. Can't tell

E. can't tell

The release of endotoxins as bacteria are destroyed by phagocytes causes the phagocytes to release tumor necrosis factor (TNF) the life-threatening loss of blood pressure occuring due to the action of TNF is called __________.

Endotoxic shock

Most pathogens that gain access through the skin by _________

Entering through hair folicles and sweat ducts

-Produce toxic protein against PARASITES

Eosinophil

-One of the formed elements - Transport Oxygen

Erythrocytes

antibody structure: stem is called the ___ region

FC

If bacteria A and B have LD50 values of 109 and 1010, respectively, more cells of A than B will be needed to kill the host. T/F

False

If bacteria attach to host tissue, they will cause disease. T/F

False

Microbes are more likely to enter the body through the skin than through the mucous membranes. T/F

False

Most host damage resulting from bacterial infection is the result of direct damage by the microbe. T/F

False

The same disease symptoms result, regardless of how a particular microbe enters the body. T/F

False

The stem of the Y-shaped antibody monomer is called the _____ region

Fc

What cell structure does Neisseria gonorrhoeae use to attach and enter host epithelial cells?

Fimbriae

-Intact skin -Mucous membranes & secretions -Normal Microbiota All of these form which line of defense ?

First line of Defense

-Portal of entry -Enter by consuming contaminated food and water -Hepatitis A, typhoid fever

GI tract

-portal of entry -Transmitted sexually ex: HIV, Herpes, gonorrhea

Genitourinary tract

Which of these diseases cannot be prevented by toxoids? 1. botulism 2. tetanus 3. gram-negative septic shock 4. diphtheria

Gram negative septic shock

Antibiotics can lead to septic shock if used to treat

Gram-negative bacterial infections

Which one of these is not an example of the parenteral route? 1. insect bite 2. cut 3. injection 4. hair follicle

Hair follicle

Which one of the following virulence factors contributes most to the spread of disease in the body? 1. hyaluronidase 2. hemolysin 3. endotoxin production 4. siderophore production

Hyaluronidase

The dose of microbes required to produce a measurable infection in half of the animals tested is referred to by the abbreviated term __________.

ID- 50

-Infectious dose for 50% of test population -Indicates the virulence of an organism - does requires to infect 50% of population

ID50

Structure: Dimer Total serum: 13% Location: Secretions ( tears, saliva , mucus) Function: localized protection on mucosal surface

IgA

Structure: Monomer Total serum: 0.02% Location: B cell surface, blood, lymph Function: serum function unknown , b cell surface immune response

IgD

Structure: Monomer Total Serum: 0.002% Location: Bound to mast and Basophil cells Function: allergic reactions , parasitic worms

IgE

Structure- Monomer ( 4 protein chain) Total Serum: 80% Location: blood, lymph, intestines Function: enhances phagocytosis , neutralizes toxins , protects fetus

IgG

Structure: Pentamer ( 5 chain) Total serum: 5-10% Location: blood, lymph, b cell surface Function: first responders/antibodies to initial infection , AGGLUTINATING machines

IgM

Fibrin clots can be dissolved by enzymes called _________.

Kinase

-lethal dose for 50% of test population -Dose required to kill 50% of test animals -THE SMALLER THE ____ THE MORE LETHAL THE TOXIN IS !!

LD50

- One of the Formed elements -Fight infection

Leukocytes

Host cells transformed by viral infection may ________.

Lose contact inhibition

-Natural killer cells T and B cells -Found in tonsils , spleen , red bone marrow and lymph nodes - Produce antibodies , destroys target cell by cytolysis (breaking down)

Lymphocytes

Lysogenic bacterial cells may express prophage DNA causing them to take on different characteristics in a process referred to as _______________.

Lysogenic conversion

Which of these is a cell wall component that contributes to invasiveness? 1. endotoxin 2. hemolysin 3. M protein 4. coagulase

M protein

Collection of genes that encode molecules of of genetically diverse glycoproteins.

MHC

-Found on nucleated cell of body Plasma membranes

MHC I

-Identify self -Prevents immune system from attacking good cells

MHC I

-Exist only on surface of Antigen-presenting cells (including b cells, macrophages) -process antigens for cD4+ t lymphocytes

MHC II

-Originate from cells that also produce granulocytes - Similar to basophils (histamine inflamm response) -Part of Innate immunity

Mast Cells

The symptoms of protozoan diseases are usually due to ________.

Metabolic waste products

-Act as macrophages (engulfs bad stuff) -phagocytosis (eats) of cells and debris

Monocytes

Traps Microbes - Ciliary escalator (trapped in mucous) - transports away from lungs (lung cookies)

Mucous Membranes

The most frequently used portal of entry for pathogens is the

Mucous membranes of the respiratory tracts

- Extracellular killer cells -part of innate immune system -DO NOT NEED Ag STIMULATION - kills virus-infect tumor cells , attack parasite terminator !!

Natural killer cells

- IgG antibodies inactivate microbe - BLOCKS attachment to host - IgG or IgM triggers COMPLIMENT SYSTEM

Neutralization

-Most common WBC -Phagocytic (ingest harmful stuff) -Can leave body and enter infected tissue

Neutrophil

- Organism is coated with antibodies - - Enhance ingestion ( PANTS THE TARGET)

Opsonization

A needlestick is an example of what portal of entry

Parenteral

Infections acquired by bites, cuts, wounds, punctures, or surgery occur via the __________ route.

Parenteral

If a patient has a deep tissue infection as the result of an animal bite on the arm, the portal of entry is described as the ________.

Parenteral route

Hepatitis B virus transmitted by a finger-stick device is transmitted by which portal of entry?

Parentral

Cholera toxin polypeptide A binds to surface gangliosides on the target cell. If the gangliosides were removed

Polypeptide B would not be able to enter the cells

Importance of Plasma cells in B cell clonal selection ?

Produces antibodies

Which of these organisms does not produce a neurotoxin? 1. Clostridium botulinum bacteria 2. Clostridium tetani bacterium 3. rabies virus 4. Alexandrium algae

Rabies virus

Based on these LD50 values, which microbe is the most virulent? Assume each bacterium enters through the appropriate portal of entry. 1. Cryptosporidium-50 cells 2. Shigella-10 cells 3. E. coli O157-1000 cells 4. Vibrio cholerae-108 cells

Shigella 10 cells

Which of these substances does not protect a bacterium from phagocytosis? 1. leukocidins 2. siderophores 3. capsule 4. M protein

Siderophores

Toxins that stimulate proliferation of T cells non-specifically and provoke intense immune responses are called _________.

Superantigens

Require T cells -Ag presents with MHC to T-helper -T-helper produces cytokines that activate b cells -strong immune response

T cell dependent antigen

-Bases of cellular immunity

T cells

______ are best at fighting viruses

T cells

___________ Mature under influence of thymus

T cells

-CD8+ -Target cells are self carry endogenous Ags -Activate CTLs induce Apoptosis ( program death) -CTL releases perforin (forms pores) and granzymes ( protease) type T cell is this ?

T cytotoxic cells

-These cells are CD4+ -Recognize Ags and MHC II on APCs - Help produce cytokines -differentiate into Th1, Th2 and Memory cells What type of T cell is this ?

T helper cells

- Ag stimulate B cells without T cells -multiple subunits bind to multiple B cells -Weaker immune response IgM and No memory cells

T independent

-Produces IFN ( cell mediated immunity, macrophage)

Th1

Injectable drugs are tested for endotoxins by

The limulus amoebocyte lysate test

The presence of endotoxins in a sterile fluid indicates ________. 1. gram-positive bacteria are growing 2. gram-negative bacteria are growing 3. the fluid is not sterile 4. the presence of gram-negative cell walls

The presence of gram-negative cell walls

Symptoms of helminthic diseases are usually due to ________.

The presence of the parasite

-One of the formed elements -Clot formation

Thrombocytes

_____ are toxins modified to retain their ability to induce antibody formation but lose their toxicity.

Toxoids

Siderophores are bacterial proteins that compete with animal ________

Transferrin

Accumulations of viral proteins and nucleic acids inside infected host cells are called inclusion bodies. T/F

True

Adhesin molecules can vary in structure among strains of a given bacterial species. T/F

True

Although some pathogens cause disease after entering the body via food and water consumption, many such microbes are killed by chemicals involved in the digestive process. T/F

True

Patient symptoms may worsen after antibiotic treatment of infections caused by gram-negative bacteria due to the sudden release of endotoxins. T/F

True

The glycocalyx (capsule/slime layer) can affect bacterial virulence by allowing attachment and by hindering phagocytosis. T/F

True

the extent of pathogenicity

Virulence

the ID50 is _______

a dose that will cause an infection in 50% of the test population

- Immunity to a specific Pathogen -Has Memory to specific pathogen

adaptive immunity

antibody structure: aways the same for particular class of -___

antibiotics

-Interacts with specific regions on antigens called epitopes or antigetic determinats

antibody

-Made of 2 light and 2 heavy chains -2 sections at end are variables bind epitopes

antibody structure

-Substance that causes the body to produce a specific antibody or sensitized T cells

antigen

T cells and B cells respond to specific _______ on the surface .

antigen receptors

Plasma cells are formed after the proliferation of which type of cell ?

b cell

The scum that builds up on shower doors, the formation of dental plaque on teeth, and the algae growth on the walls of swimming pools are all examples of _______.

biofilms

-Due to T cells -T cells mature in the thymus -Effective against intracellular pathogens , virus infected cells, cancer and intracellular parasites

cellular immunity

-stem cells differentiate int mature B cells -B cell III complex w/ specific antigen to hunt -Some b cells active duty (plasma) , some reserve (memory) -Plasma cells leak antibodies in circulation

clonal selection

-One organism (microbe) benefits and host unharmed -May be opportunistic pathogen HARMLESS UNLESS CONDITION CHANGES ?

commensal microbiota

many of organisms of our own biota make up this

commensalism

antibody structure: The stem and lower parts of arms are called _____

constants

T cells secrete what

cytkines

-membrane disrupting LYSE HOST!

cytotoxin

-They are the PRINCIPLE antigen-Presenting cell for T cells Engulf microbe--> degrade them--Present to T cell in lymph nodes

dendritic cels

Saxitoxin is produced by ________.

dinoflagellates

-the part of an antigen molecule to which an antibody attaches itself.

epitopes

Generally, antibodies recognize and interact with specific regions on antigens called ?

epitopes

Which one of these substances should not be produced at the same time as coagulase? 1. fibrinolysin 2. fimbriae 3. capsules 4. hemolysin

fibrinolysin

__________ are bacterial enzymes that lyse erythrocytes.

hemolysins

-Due to antibody produced by B cells -B cells mature in bone marrow -Effective against freely circulating viruses and bacteria (in blood stream)

humoral immunity

- Our ability to ward of disease -Protect against pollen, drugs, foods, chemicals

immunity

- Defense against Any pathogen -Present at birth -Provide rapid response against disease

innate immunity

resistance to pathogens conferred by barriers, chemical, cells, and process that remain unchanged upon subsequent infections with the same pathogens

innate immunity

penetrates or evade -destroys leukocytes

leukocidins

What are the 3 formed elements ?

leukocytes, erythrocytes, and thrombocytes

Chemical factor -In Perspiration (tears, saliva, urine) -Digest Peptidoglycan

lysozyme

Which chemical factor digests peptidoglycan in perspiration, tears and saliva ?

lysozyme

-Penetrate or evade -Heat and acid resistant mediates attachment to epithelial cells and prevents phago

m protein

These B or T cells are inactive until a second encounter. - Second encounter is faster due to knowing the enemy what type of cells are these ?

memory cells

Whats the distance that airborne transmissions can travel ?

more than 1 meter

Whats the importance of clones in B cell clonal selection IgM production first

multiple fighters with same target

Penetrates or evade -prevents phago

mycolicacid

IgG antibodies inactivate microbes by blocking their attachment to host cells in the binding known as

neutralization

List of Leukocytes from Most to Least Hint: Never Let Monkeys Eat Bananas

nlmeb

-markers on cells and tissues which may have entered the organism -eg. transplant, virus, bacteria, recognizes as foreign and as a result will initiate an immune response. -STRANGER DANGER ATTACK!

nonself antigen

________ are markers on cells and tissues which may have entered the organism -eg. transplant, virus, bacteria,

nonself antigen

Prevent pathogens from colonizing host by competing for nutrients

normal microbiota

Which would be the most unlikely location to find adhesin molecules on a newly discovered bacterium? 1. glycocalyx 2. fimbriae 3. capsule 4. ribosomes 5. cell wall

ribosomes

-Chemical factor -oil secretion from skin that is antifungal ?

sebum

- Self antigens are marker molecules on the surface of individual cells indicate that cell to be a part of the organism. -NO STRANGER DANGER

self antigen recognition

________ are marker molecules on the surface of individual cells

self antigens

Which one of these bacterial proteins can take iron from human lactoferrin? 1. protease 2. siderophore 3. hyaluronidase 4. kinase

siderophore

property that protects a type of organism from infection by pathogens of other very different organisms

species resistance

- B cell is triggered once it encounters its matching antigen -Within B cell a fragment of antigen combines with MHCII which step ?

step 1 antibody mediated

- MHC II is displayed on B cell which step is this ?

step 2 antibody mediated

-T helper recognizes complex of MHC II becomes ACTIVATED - cytokines ACTIVATE B cells what step is this?

step 3 antibody mediated

-B cell is ACTIVATED BY cytokines -Clonal expansion begins - Some become antibody producing plasma cells what step is this?

step 4 antibody mediated

-The relationship btw normal microbiota and host is called ?

symbiosis

- Carry CD25 on surface -subset of CD4+ -SUPRESSES T CELLS AGINST SELF ! COMBAT AUTOIMMUNITY

t regulatory cells

-Activates Eosinophils and B cells to produce IgE

th2

- # of antigen binding sites determines ?

valence