Host Defenses Ch 14 Microbiology
Neutrophils, also called polymorphonuclear neutrophils (PMNs), make up
- 55% to 90% of the circulating leukocytes—about 25 billion cells in the circulation at any given moment. -The main work of the neutrophils is in production of toxic chemicals and in phagocytosis at the early stages of a response. Their high numbers in both the blood and tissues suggest a constant challenge from resident microbiota and environmental sources. -Most of the cytoplasmic granules carry digestive enzymes and other chemicals that degrade the phagocytosed materials -The average neutrophil lives only about 8 days, spending much of this time in the tissues and only about 6 to 12 hours in circulation.
Which of the following processes are components of the second line of defense?
-Antimicrobial proteins -Phagocytosis -Inflammation -Fever
Which of the following IS a nonspecific host defense?
-Chemical barriers -Physical barriers -Genetic differences
Which of the following are main functions of the inflammatory response?
-Destroy microbes and block their further invasion. -Mobilization and attraction if immune components to the site of infection or trauma. -Repair of damaged tissues
Which of the following are medical terms for swelling?
-Edema -Tumor (Is the Latin term for swelling, edema would be more commonly used in the clinical setting)
Inflammatory mediators cause which of the following host responses?
-Fever -Stimulation of lymphocytes -Symptoms of allergy
Which of the following processes are components of the second line of defense?
-Inflammation -Phagocytosis -Fever -Antimicrobial proteins
Give the correct order for the stages of complement activation.
-Initiation -Amplification -Polymerization -Membrane attack
Which of the following are NOT exogenous pyrogens?
-Interferon is produced and secreted by host cells and thus is not an exogenous pyrogen. -Histamine is a vasoactive mediator but not a pyrogen. -Interleukin-1 is an endogenous pyrogen from the host cell, not from the bacterial outer membrane like LPS -TNF is an endogenous pyrogen from the host cell, not from the bacterial outer membrane like the LPS.
Which are agranulocytic white blood cells?
-Monocytes and Lymphocytes
Although lymphocytes are the cornerstone of the third line of defense, their origin and morphology are described here so their relationship to the other blood components is clear. Lymphocytes are the second most common
-WBC in the blood, comprising 20% to 35% of the total circulating leukocytes. -One estimate suggests that about one-tenth of all adult body cells are lymphocytes, exceeded only by erythrocytes and fibroblasts. -Lymphocytes exist as three functional types—the bursal-equivalent, or B lymphocytes (B cells, for short); the thymus-derived, or T lymphocytes (T cells, for short); and a set called null cells.
Agranulocytes (agranular leukocytes) have
-globular, nonlobed nuclei and lack prominent cytoplasmic granules when viewed with the light microscope. The two general types are lymphocytes and monocytes.
The role of the eosinophil (ee"-oh-sin'-oh-fil) in the immune system is complicated. The eosinophil granules contain
-peroxidase, lysozyme, and other digestive enzymes, as well as toxic proteins and inflammatory chemicals. -The protective action of eosinophils is to attack and destroy large eukaryotic pathogens, but they are also involved in the formation of fetal tissue as well as in inflammation and allergic reactions. -Among their most important targets are helminth worms and fungi. -Eosinophils are among the earliest cells to accumulate near sites of inflammation and allergic reactions, where they attract other leukocytes and release chemical mediators.
The hydrolytic enzyme lysozyme is found in:
-saliva -sebum
Basophils are the scarcest type of leukocyte, making up less than 0.5% of the total circulating WBCs in a normal individual. They share some morphological and functional similarities with
-widely distributed tissue cells called mast cells. -Mast cells are nonmotile elements bound to connective tissue around blood vessels, nerves, and epithelia; - -basophils are motile elements derived from bone marrow. circulating WBCs in a normal individual. -Basophils parallel eosinophils in many of their actions, because they also contain granules with potent chemical mediators. - Mast cells are first-line defenders against the local invasion of pathogens; they recruit other inflammatory cells; and they are directly responsible for the release of histamine and other allergic stimulants during immediate allergies
List the correct order of events in phagocytosis.
1. Chemotaxis 2. Endocytosis 3. Destruction 4. Release
Give the correct order of location for the events of hematopoiesis.
1. Yolk sac 2. Liver and lymphatic organs 3. Red bone marrow
The circulatory and lymphatic systems do what 3 things?
1. to provide an auxiliary route for the return of extracellular fluid to the circulatory system proper; 2. to act as a "drain-off" system for the inflammatory response; and 3. to render surveillance, recognition, and protection against foreign materials through a system of lymphocytes, phagocytes, and antibodies.
Which is NOT normal body temperature?
98.6 degrees Celsius
Which of the following is NOT a nonspecific host defense?
Antibody produciton
short proteins, of 12 to 50 amino acids in length, that have the ability to destroy microbes are called
Antimicrobial peptides (AMPs)
Select the nonspecific host defenses.
First and Second lines
Trauma, infection, or an immune response can trigger a nonspecific immune response called
Inflammation
___, more commonly called white blood cells, are primary infection-fighting blood cells.
Leukocytes
___are the second most predominating type of leukocyte in circulation.
Lymphocytes
Which of the following cell types are NOT involved in the third line of host defense?
Mast cells Neutrophils Macrophages
Which is engulfed by phagocytes?
Microbes, dust, and dead cells
Which of the following cell types are involved in the third line of host defense?
Natural killer cells
Which of the following are granulocytic white blood cells.
Neutrophils Basophils Eosinophils
List the predominance of circulating leukocytes from most to least.
Neutrophils, Lymphocytes, Monocytes, Eosinophils Basophils Acronym is Never Let Monkeys Eat Bananas
--- are the first phagocytes to respond to an inflammatory event and the most common leukocyte.
Neutropholis
True or false: inborn physical barriers, chemical barriers, and genetic differences are nonspecific host defense mechanisms.
True
Monocytes and lymphocytes are white blood cells known as ___ because they lack easily observed cytoplasmic granules.
agranulocytes
Monocytes and lymphocytes are white blood cells known as___ because they lack easily observed cytoplasmic granules.
agranulocytes
Genes that encode membrane receptors, protein defenses, and
barrier protections are common among species.
Which is Latin for warmth during inflammation?
calor
The third line of defense is
characterized by specific acquired immunity.
B cells were first demonstrated in and named for a special lymphatic gland of
chickens called the bursa of Fabricius, the site for their maturation in birds. -In humans, B cells mature in special bone marrow sites; humans do not have a bursa of Fab-ricius. -T cells mature in the thymus in all birds and mammals. -Both populations of cells are transported by the bloodstream and lymph and move about freely between lymphoid organs and connective tissue. -Null cells, chief among them natural killer (NK) cells, develop directly from lymphoid stem cells. They can act in concert with the specific immune response or independently of it.
Lymphocytes are the second most
common of the leukocytes and include B cells and T cells.
With respect to inflammation__ is Latin for pain
dolor
Red blood cells are called___.
erythrocytes
Agranulocytes do not have easily observed granules in their cytoplasm
examples are monocytes and lymphocytes
defecation and vomiting are considered to be components of the ______ line of defense.
first -Vomiting and defecation evacuate noxious substances or microorganisms from the digestive tract are components of the first live of defense.
Blood plasma does not contain
formed elements (cells)
A type of white blood cell with noticeable cytoplasmic granules is called a)n___.
granulocyte
inflammation (Edema is one of the classic signs of
inflammation, along with redness, heat, pain and loss of function.
A large, phagocytic white blood cell, derived from a monocyte, that leaves the circulation and plays a role in specific immune reactions while reading in tissues is called a(n) ___l
macrophage
The largest phagocytic white blood cell derived from a monocyte which is involved with specific immune reactions is called a tissue___
macrophage
The 3 main types of phagocytes are:
macrophages monocytes neutrophils
A(n)___ is any trait, factor, or receptor of a cell, virus, or molecule that makes it distinct and recognizable.
marker
A(n) ___ is a large leukocyte that can develop into a tissue macrophage.
monocyte
Lymphocytes are the second
most common of the leukocytes and include B cells and T cells
The types of granular leukocytes present in the bloodstream are
neutrophils, eosinophils, and baso-phils. All three are known for prominent cytoplasmic granules that stain with some combination of acidic dye (eosin) or basic dye (methylene blue). -Although these granules are useful diagnostically, they also function in numerous physiological events
inflammation is a ___ second line defense mechanism that acts rapidly at the local and systemic levels, against an pathogen.
nonspecific
What is the main role of neutrophils?
phagocytosis
___is a type of endocytosis in which the cell membrane actively engulfs large particles or cells into vesicles.
phagocytosis
Hair, cilia, and microvilli are ___ barriers that protect portals of entry against pathogens invading the body.
physical
The first line of defense consists of
physical and chemical barriers associated with the skin and mucous membranes. Normal biota, though not considered a physical barrier, have been found to contribute to this and other lines of defense as well.
___ is opaque matter formed during inflammation that consists of serum exudate, tissue debris, leukocytes, and microorganisms.
pus
___is opaque matter formed during inflammation that consists of serum exudate, tissue debris, leukocytes, and microorganisms.
pus
Inflammation and phagocytes are nonspecific functions that are a part of which line of immune defense?
second The second line encompasses all the nonspecific cells and chemicals found in the tissues and blood.
Nonspecific lines of defense are
second and first
Natural markers of the body that are recognized by the immune system are called _____.
self
The unbroken ___ is a formidable barrier to the entry of microbes and is classified as a component of the first line of defense.
skin
___ is/are external, confluent protective barrier.
skin
The third line of defense is characterized by
specific acquired immunity.
White blood cells are equipped with a very sensitive sense of "touch." As they sort through the tissues, they feel
surface markers that help them determine what is self and what is not. When self markers are recognized, no response occurs. However, when nonself is detected, a reaction to destroy it is mounted.
The third line of defense
the specific immune response, is customized to react to specific antigens of a microbial invader
specific lines of defense are
third
True or false: Neutrophils are the first phagocytes to act in inflammation.
true
With respect to inflammation, ___ is the Latin term for swelling.
tumor
The flow of ___flushes the urethra.
urine
___is a term for the widening of blood vessels that increases blood flow to the an injured area.
vasodilation
Leukocytes are ___blood cells.
white
The liquid connective tissue consisting of erythrocytes, leukocytes, and platelets suspended in plasma is called___.
whole blood
