Ch 16 hw

indicate the correct order of events of complement activation via the classical pathway.

1) C1 interacts with antibody that is bound to pathogen 2) C1 cleaves C2 and C4 3) C2a and C4b combine to form an enzyme 4) C3 split into C3a and C3b

As you can see from this activity, the immune system is very complex and is made of many components. In this section, place each immune component in the appropriate place either 1st line, 2nd line or 3rd line of defense. sweat sebum (oil) fever NK cells T lymphocytes B lymphocytes

1st line: sweat sebum (oil) 2nd line: fever NK cells 3rd line: T lymphocytes B lymphocytes

Part complete You now know that once complement is activated, all outcomes occur. With respect to the membrane attack complex (MAC), which is most likely to occur once all of the C9 proteins insert into the bacterial plasma membrane? The bacterium will repair the membrane and eventually recover. More C1 will become activated because C9 is an activator of C1 proteins. A neutrophil will engulf the bacterium because C9 acts as an opsonin. A hole will form in the bacterium, allowing water to rush into the cell and causing lysis.

A hole will form in the bacterium, allowing water to rush into the cell and causing lysis.

TLRs attach to all of the following EXCEPT flagellin. PAMPs. AMPs. peptidoglycan. LPS.

AMPs

In the Case of Classical Activation, Which Outcome Is Likely to Occur? Membrane attack complex will form. Inflammation will be stimulated. Pathogens will become opsonized. All of the listed outcomes will occur.

All of the listed outcomes will occur.

Part complete As mentioned previously, the second line of defense is activated when the first line of defense fails. In Part A, you identified one of these defenses as inflammation, which occurs when the body responds to a foreign antigen and increases fluid accumulation in a specific area. An added benefit of this excess fluid is that it also brings immune cells to the area to aid clearance of foreign antigens. In Julie's situation, that added fluid would bring immune cells to prevent any microbial infections that could be caused if microbes were introduced when she cut her finger. Which of the following cell types is NOT part of the second line of defense? eosinophils B cells mast cells basophils

B cells

Which of the following statements concerning phagocytosis is true? Adherence always requires opsonization. Bacteria are digested when the phagosome fuses with a lysosome. Phagocytes ingest microorganisms by using protein transporters that are specific to the bacteria Phagocytes cannot ingest microorganisms unless they are coated with antibodies.

Bacteria are digested when the phagosome fuses with a lysosome.

T/F An example of a TLR would be peptidoglycan found in the cell wall of gram-positive bacteria.

False

Which of the following statements about innate immunity is true? It involves the activity of B and T cells. The innate immune response does not have a mechanism for detecting invading microorganisms. It is activated only in response to tissue damage or a signal from an infected cell Innate immunity involves specific recognition of microorganisms via a memory response. Innate immunity is present at birth and provides a fast response that involves first- and second-line defenses.

Innate immunity is present at birth and provides a fast response that involves first- and second-line defenses.

indicate whether the statement applies to opsonization, inflammation stimulation, or direct cell lysis. Macrophages and neutrophils are attracted to C3 protein molecules bound to the pathogens, making them easier to phagocytize. C3b fragments bind to the surface of pathogens. C5a fragments recruit immune cells to the site of infection. Neutrophils are attracted to the area and arrive via diapedesis. transmembrane proteins are recruited to the pathogen. MAC introduces holes to the bacterial cell membrane. C9 is polymerized into a circular-shaped complex on the pathogen surface.

Opsonization: C3b fragments bind to the surface of pathogens. Macrophages and neutrophils are attracted to C3 protein molecules bound to the pathogens, making them easier to phagocytize. Inflammation stimulation: C5a fragments recruit immune cells to the site of infection. Neutrophils are attracted to the area and arrive via diapedesis. Direct cell lysis: Multiple transmembrane proteins are recruited to the pathogen. MAC introduces holes to the bacterial cell membrane. C9 is polymerized into a circular-shaped complex on the pathogen surface.

Part complete What does a phagocyte attach to on a microorganism? PRR TLR Nucleus PAMPs

PAMPs

Part complete Digestion of microorganisms occurs in ________________ Phagosomes Phagolysosomes Complement proteins Lysosomes

Phagolysosomes

Which of the following statements is TRUE? Complement activity is antigen-specific. Complement increases after vaccination. Factors B, D, and P cause cytolysis. The complement system can detect and destroy invading microorganisms All of the complement proteins are constantly active in serum.

The complement system can detect and destroy invading microorganisms

One of the outcomes of complement activation is the stimulation of inflammation. Inflammation may result in redness, heat, swelling, and pain. Of the following, which is NOT a way that inflammation helps the body clear infection? Inflammation allows for more macrophages to come to the area of infection. The redness is caused by more blood flowing to the infected area. Inflammation causes diapedesis, which allows more neutrophils to the area of infection. The swelling of the infected area destroys pathogens by squishing them.

The swelling of the infected area destroys pathogens by squishing them.

What is the role of opsonins? They aid in the formation of the phagolysosome. They create "handles" that make it easier for the pseudopods of phagocytes to attach to the microbe invader. They attract phagocytes to the location of infection. They are present on the surface of phagocytes to facilitate adherence and ingestion.

They create "handles" that make it easier for the pseudopods of phagocytes to attach to the microbe invader

Part complete Margination refers to the chemotactic response of phagocytes. the movement of phagocytes through walls of blood vessels. dilation of blood vessels. adherence of phagocytes to the lining of blood vessels. the adherence of phagocytes to microorganisms.

adherence of phagocytes to the lining of blood vessels.

Part complete All of the following are components of the inflammatory process EXCEPT release of histamines and prostaglandins. antibody synthesis. chemotaxis. dilation of blood vessels. diapedesis.

antibody synthesis.

Lysozyme and the antibiotic penicillin have similar mechanisms of action in that they both cause damage to the bacterial DNA. capsule. cell wall. cell membrane. ribosomes.

cell wall

The process by which a phagocyte moves toward a chemical signal at the site of an infection is called adherence. chemotaxis. exocytosis. digestion. elimination.

chemotaxis

Part complete Which of the following is mismatched? pus - tissue debris and dead phagocytes in a white or yellow fluid diapedesis - movement of leukocytes between capillary walls cells out of blood and into tissue chemotaxis - chemical degradation inside a phagolysosome scab - dried blood clot over injured tissue abscess - a cavity created by tissue damage and filled with pus

chemotaxis - chemical degradation inside a phagolysosome

Unbroken skin poses a substantial barrier to microbes. All of the following contribute to this barrier except _____________. the tightly-packed layer of dead, keratinized cells dryness of the skin fatty acids within sebum complement proteins found in perspiration

complement proteins found in perspiration

Which of the following phagocytic processes occurs last in the sequence? Chemotaxis of the phagocyte to the site of infection Digestion Formation of the phagolysosome Adherence

digestion

If one is examining a blood smear from a patient with a parasitic worm infection, which of the following leukocytes would be found in increased numbers? eosinophils basophils monocytes lymphocytes

eosinophils

The swelling associated with inflammation decreases when the fluid is transported into macrophages. is lost as perspiration. goes into lymph capillaries. returns to the blood. is excreted in urine.

goes into lymph capillaries.

Part complete Which of the following is an effect of opsonization? inflammation increased adherence of phagocytes to microorganisms cytolysis increased margination of phagocytes increased diapedesis of phagocytes

increased adherence of phagocytes to microorganisms

Julie is preparing vegetables for dinner and accidentally cuts her finger. She washes it with soap and water before covering it with a bandage. A short while later, Julie notices that her finger is red, swollen, warm to the touch, and very painful. Which of the following describes the process going on in Julie's finger? inflammation complement fever phagocytosis

inflammation

Phagocytes utilize all of the following to optimize interaction with (getting to and getting hold of) microorganisms EXCEPT chemotaxis. trapping a bacterium against a rough surface. lysozyme. complement. opsonization.

lysozyme.

Part complete Which of the following exhibits the highest phagocytic activity? erythrocytes macrophages eosinophils neutrophils basophils

macrophages

Heparin is a naturally occuring anticoagulant produced by macrophages. neutrophils. eosinophils. mast cells and basophils. skin cells.

mast cells and basophils

Macrophages arise from which of the following? monocytes lymphocytes eosinophils neutrophils basophils

monocytes

Innate immunity includes all of the following EXCEPT phagocytosis. inflammation. activation of complement. production of interferon. production of antibody.

production of antibody.

Inflammation is part of the second line of defense that is activated when the first line of defense is breached. Julie's first-line defenses were damaged when her injury occurred. Which of the following represents the first line of defense? white blood cells red blood cells skin and mucous membranes platelets

skin and mucous membranes

All of the following are true regarding NK cells EXCEPT they release toxic substances that cause cell lysis or apoptosis. they destroy infected body cells by phagocytosis. they are a type of lymphocyte. they have the ability to kill infected body cells and some tumor cells.

they destroy infected body cells by phagocytosis

Which of the following statements about fixed macrophages is FALSE? They develop from neutrophils. They are found in certain tissues and organs They are mature monocytes They are cells of the mononuclear phagocytic system. They gather at sites of infection

they develop from neutrophils

Normal microbiota provide protection from infection in each of the following ways EXCEPT they produce lysozyme. they make the chemical environment unsuitable for nonresident bacteria. they compete with pathogens for nutrients. they compete with pathogens for space and adherence. they produce antibacterial chemicals.

they produce lysozyme

Part complete The function of the "ciliary escalator" is to trap microorganisms in mucus in the upper respiratory tract. propel inhaled dust and microorganisms away from the mouth, toward the lower respiratory tract. remove microorganisms from the gastrointestinal tract. remove microorganisms from the lower digestive tract. trap inhaled dust and microorganisms in mucus and propel it away from the lower respiratory tract.

trap inhaled dust and microorganisms in mucus and propel it away from the lower respiratory tract.

All of the following occur during inflammation. What is the first step? margination repair phagocyte migration diapedesis vasodilation

vasodilation