exam 4 BIOL 2460 review

Which of the following would be a sign of an infection?

fever

Which of the following is an example of a noncommunicable infectious disease?

food poisoning due to a preformed bacterial toxin in food

During an oral surgery, the surgeon nicked the patient’s gum with a sharp instrument. This allowed Streptococcus, a bacterium normally present in the mouth, to gain access to the blood. As a result, the patient developed bacterial endocarditis (an infection of the heart). Which type of disease is this?

iatrogenic

Which period is the stage of disease during which the patient begins to present general signs and symptoms?

prodromal

A communicable disease that can be easily transmitted from person to person is which type of disease?

contagious

Which of the following is a pathogen that could not be identified by the original Koch’s postulates?

Human immunodeficiency virus

Pathogen A has an ID₅₀ of 50 particles, pathogen B has an ID₅₀ of 1,000 particles, and pathogen C has an ID₅₀ of 1 × 10⁶ particles. Which pathogen is most virulent?

pathogen A

Which of the following choices lists the steps of pathogenesis in the correct order?

exposure, adhesion, invasion, infection

Which of the following would be a virulence factor of a pathogen?

a surface protein allowing the pathogen to bind to host cells

You have recently identified a new toxin. It is produced by a gram-negative bacterium. It is composed mostly of protein, has high toxicity, and is not heat stable. You also discover that it targets liver cells. Based on these characteristics, how would you classify this toxin?

exotoxin

Which of the following applies to hyaluronidase?

It acts as a spreading factor.

Phospholipases are enzymes that do which of the following?

degrade cell membranes to allow pathogens to escape phagosomes

Which of the following is a major virulence factor for the fungal pathogen Cryptococcus?

capsule

Which of the following pathogens undergoes antigenic variation to avoid immune defenses?

Plasmodium

A difference between an acute disease and chronic disease is that chronic diseases have an extended period of __________.

illness

A person steps on a rusty nail and develops tetanus. In this case, the person has acquired a(n) __________ disease.

noncommunicable

A(n) __________ pathogen causes disease only when conditions are favorable for the microorganism because of transfer to an inappropriate body site or weakened immunity in an individual.

opportunistic

The concentration of pathogen needed to kill 50% of an infected group of test animals is the __________.

LD₅₀

A(n) __________ infection is a small region of infection from which a pathogen may move to another part of the body to establish a second infection.

focal

Cilia, fimbriae, and pili are all examples of structures used by microbes for __________.

adhesion

The glycoprotein adhesion gp120 on HIV must interact with __________ on some immune cells as the first step in the process of infecting the cell.

CD4

Adhesins are usually located on __________ of the pathogen and are composed mainly of __________ and __________.

surface; proteins; sugars

The Shiga and diphtheria toxins target __________ in host cells.

protein synthesis

Antigenic __________ is the result of reassortment of genes responsible for the production of influenza virus spike proteins between different virus particles while in the same host, whereas antigenic __________ is the result of point mutations in the spike proteins.

shift; drift

Candida can invade tissue by producing the exoenzymes __________ and __________.

protease and phospholipase

The larval form of Schistosoma mansoni uses a __________ to help it gain entry through intact skin.

protease

Which is the most common type of biological vector of human disease?

arthropods

A mosquito bites a person who subsequently develops a fever and abdominal rash. What type of transmission would this be?

biological vector transmission

Cattle are allowed to pasture in a field that contains the farmhouse well, and the farmer’s family becomes ill with a gastrointestinal pathogen after drinking the water. What type of transmission of infectious agents would this be?

vehicle transmission

A blanket from a child with chickenpox is likely to be contaminated with the virus that causes chickenpox (Varicella-zoster virus). What is the blanket called?

fomite

Which of the following would NOT be considered an emerging disease?

Tuberculosis

Which of the following would NOT be considered a reemerging disease?

West Nile virus fever/encephalitis

Which of the following factors can lead to reemergence of a disease?

A period of decline in vaccination rates

Why are emerging diseases with very few cases the focus of intense scrutiny?

They are increasing and therefore not controlled

The ________ collects data and conducts epidemiologic studies in the United States.

Centers for Disease Control and Prevention, or CDC

________occurs when an infected individual passes the infection on to other individuals, who pass it on to still others, increasing the penetration of the infection into the susceptible population.

Propagated spread

A batch of food contaminated with botulism exotoxin, consumed at a family reunion by most of the members of a family, would be an example of a ________ outbreak.

point source

A patient in the hospital with a urinary catheter develops a bladder infection. This is an example of a(n) ________ infection.

nosocomial or healthcare-associated

A ________ is an animal that can transfer infectious pathogens from one host to another.

vector

The ________ collects data and conducts epidemiologic studies at the global level.

WHO (World Health Organization)

Which of the following best describes the innate nonspecific immune system?

a generalized and nonspecific set of defenses against a class or group of pathogens

Which of the following constantly sheds dead cells along with any microbes that may be attached to those cells?

epidermis

Which of the following uses a particularly dense suite of tight junctions to prevent microbes from entering the underlying tissue?

the blood-brain barrier

Which of the following serve as chemical signals between cells and stimulate a wide range of nonspecific defenses?

cytokines

Bacteriocins and defensins are types of which of the following?

antimicrobial peptides

Which of the following chemical mediators is secreted onto the surface of the skin?

sebum

Identify the complement activation pathway that is triggered by the binding of an acute-phase protein to a pathogen.

lectin

Histamine, leukotrienes, prostaglandins, and bradykinin are examples of which of the following?

chemical mediators that promote inflammation

White blood cells are also referred to as which of the following?

leukocytes

Hematopoiesis occurs in which of the following?

bone marrow

Granulocytes are which type of cell?

leukocyte

PAMPs would be found on the surface of which of the following?

pathogen

________ on phagocytes bind to PAMPs on bacteria, which triggers the uptake and destruction of the bacterial pathogens?

PRRs

Which of the following best characterizes the mode of pathogen recognition for opsonin-dependent phagocytosis?

A pathogen is first coated with a molecule such as a complement protein, which allows it to be recognized by phagocytes.

Which refers to swelling as a result of inflammation?

edema

Which type of inflammation occurs at the site of an injury or infection?

acute

The muscular contraction of the intestines that results in movement of material through the digestive tract is called ________.

peristalsis

______ are the hair-like appendages of cells lining parts of the respiratory tract that sweep debris away from the lungs.

cilia

Secretions that bathe and moisten the interior of the intestines are produced by _______ cells.

goblet

________ are antimicrobial peptides produced by members of the normal microbiota.

bacteriocins

________ is the fluid portion of a blood sample that has been drawn in the presence of an anticoagulant compound.

plasma

The process by which cells are drawn or attracted to an area by a microbe invader is known as ________.

chemotaxis

Platelets are also called ________.

thrombocytes

The cell in the bone marrow that gives rise to all other blood cell types is the ________.

pluripotent hematopoietic stem cell (HSC)

PMNs are another name for ________.

neutrophils

Kupffer cells residing in the liver are a type of ________.

macrophage

_____________ are similar to basophils, but reside in tissues rather than circulating in the blood.

mast cells

________, also known as diapedesis, refers to the exit from the bloodstream of neutrophils and other circulating leukocytes.

extravasation

Toll-like receptors are examples of ________.

pattern-recognition receptors (PRRs)

A(n) ________ is a walled-off area of infected tissue that exhibits chronic inflammation.

granuloma

The ________ is the part of the body responsible for regulating body temperature.

hypothalamus

Heat and redness, or ________, occur when the small blood vessels in an inflamed area dilate (open up), bringing more blood much closer to the surface of the skin.

erythema