Anatomy Exam Flashcards (take 2) (copy)

what are the primary lymphoid organs

red bone marrow and thyms

what is the shared role of the primary lymphoid organs?

where B and T cells mature

what is red bone marrow the site of?

B lymphocyte maturation

what is the thymus the site of?

T lymphocyte maturation

what is the shared role of the secondary lymphoid organs?

where B and T cells activate

what are the secondary lymphoid organs?

lymph nodes, spleen, mucosa-associated lymphoid tissue (MALT)

what are examples of MALT?

tonsils, appendix, Peyer’s patches

what are the vessels of the lymphatic system in the order in which lymph flows?

1. lymphatic capillaries

2. collecting lymphatic vessels

3. lymphatic trunks

4. lymphatic ducts

where does lymph enter the venous system?

at the junction of the internal jugular vein and subclavian vein on the same side

how is lymph moved through lymphatic vessels?

pumping action of skeletal muscles, respiratory pumps, one-way valves, and smooth muscle contraction

what are the lymphatic ducts?

right lymphatic duct and thoracic duct

what does the right lymphatic duct drain lymph from?

right upper body

what does the thoracic duct drain lymph from?

rest of the body

what are the immune cells found in the lymphatic system?

T and B lymphocytes, macrophages, and dendritic cells

what are the supporting cells found in the lymphatic system?

reticular cells

what is the connective tissue found in lymphoid organs?

reticular loose connective tissue

what is the spleen the site for?

division of lymphocytes and immune surveillance

what is the primary function of the spleen?

filters pathogens and old red blood cells from the blood

what is the function of MALT?

first line of defense in the immune system; responds against pathogens that enter through mucosal surfaces

what is the function of the tonsils?

traps and removes pathogens entering the pharynx in food or inhaled air

what are the 2 functions of lymph nodes?

cleanse lymph and activate immune system

how do lymph nodes cleanse lymph?

they use macrophages to remove and destroy microorganisms and debris

how do lymph nodes activate the immune system?

antigens in the lymph activate lymphocytes in lymph nodes

where is the spleen located?

left side of abdominal cavity beneath the diaphragm

how does the spleen filter blood?

• macrophages remove pathogens and debris

• recycles and stores iron from old RBCs

• stores platelets and monocytes

what are the 4 basic functions of the immune system?

• recognizes and eliminates pathogens

• disposes of aging cells/debris

• wound healing

• eliminates mutated cells

what is immunity?

the body’s ability to resist and defend against infectious organisms and other harmful substances

what is the immune response?

the body’s reaction to infectious or harmful substances

what is resistance?

the ability of the body to maintain immunity

what are the components of the innate defense system?

external body membranes and internal defenses

what are the components of the adaptive defense system?

humoral (antibody-mediated) immunity and cellular immunity

what are the components of the surface barriers within the innate defense system?

skin and mucous membranes

what are the components of the internal defenses within the innate defense system?

phagocytes, natural killer cells, inflammation, antimicrobial proteins, and fever

how do secretions of sebaceous and sweat glands contribute to the surface barrier?

they contain bactericidal chemicals, enzymes, and antibodies that wash away microorganisms and harmful chemical agents

what are lysozymes?

antimicrobial enzymes that destroy bacteria found in saliva, respiratory mucus, and lacrimal fluid of the eye

what are defensins?

antimicrobial peptides secreted by mucous membranes and skin that attack bacteria by forming holes in the plasma membrane of bacteria

what do granules of neutrophils contain?

hydrolytic enzymes and antimicrobial proteins, such as defensins

what are neutrophils?

active phagocytes that attack bacteria

what is the primary mode of attack of eosinophils?

exocytosis of toxic compounds such as nitric oxide

what can eosinophils attack?

multicellular parasites

what are macrophages?

large, active phagocytes

what are macrophages derived from?

monocytes

what are the two types of macrophages?

free and fixed

what are free macrophages?

macrophages that wander throughout tissue

what are fixed macrophages?

macrophages that reside in specific tissues and stay within those tissues

what are the 4 different types of fixed macrophages?

histiocytes, microglia, stellate macrophages, and alveolar macrophages

where are histiocytes found?

in connective tissues, usually on collagen or reticular fibers

where is microglia found?

in the central nervous system

where are Stellate macrophages found?

in liver sinusoids

where are alveolar macrophages found?

in the alveoli

what is the role of opsonization in phagocytosis?

phagocytes are coated with opsonins, allowing them to attack bacteria with capsule that makes binding more difficult

where are natural killer cells found?

circulating through lymph and blood

are natural killer cells specific?

no

which cells to natural killer cells lyse and kill?

cancer cells and virus-infected body cells

how do natural killer cells kill?

through direct contact with target cells and the release of perforin

what are the 4 beneficial effects of inflammation?

• prevents spread of damaging agents

• disposes of cell debris and pathogens

• alerts adaptive immune system

• sets stage for repair

what are the 4 signs of inflammation?

redness, heat, swelling, pain

what is the inflammatory chemical released by mast cells?

histamine

what are the 4 inflammatory chemicals?

histamines, kinins, prostaglandins, and complement proteins

what are the 3 functions of inflammatory chemicals?

dilate local arterioles, make local capillaries leakier, and attract leukocytes to area

what causes pain in the area of inflammation?

exudate leaks from capillaries into tissue, producing swelling that causes pain due to increased pressure on nerve endings.

how does Aspirin decrease pain during inflammation?

they inhibit prostaglandins, which in turn reduces pain

how does exudate affect the lymphatic system?

it washes foreign material into lymphatic vessels which process fluid in lymph nodes

what does exudate deliver that aids in the immune response?

complement proteins and clotting factors

how does clot formation triggered by exudate aid in the immune response?

it isolates the injured area and prevents spread of foreign material

what are the 4 steps in the mobilization of leukocytes to the injured area?

1. leukocytosis

2. margination

3. diapedesis

4. chemotaxis

what happens during leukocytosis?

injured cells release leukocytosis factors which induce neutrophils to enter blood from red bone marrow

what happens during margination?

CAMs on endothelial cells of inflamed tissue signal the site of injury, then inflammatory chemicals activate CAMs on neutrophils, triggering them to bind to endothelial cells of capillaries in the inflamed tissue

what happens during diapedesis?

neutrophils flatten and squeeze through endothelial cells of capillary wall

what happens during chemotaxis?

neutrophils and other white blood cells migrate up gradient of chemotactic agents released during inflammation and neutrophils gather at the site of injury within an hour

how do interferons protect against viral infections?

they are released by infected cells and bind to receptors on nearby cells, stimulating them to produce proteins that block protein synthesis and degrade the RNA of the virus

what are the 2 functions of complement proteins?

enhance inflammation, lyse and kill bacteria and other cells

what are the 3 properties of the adaptive defense system?

specific, systemic, has memory

what is the function of cytotoxic T cells?

directly attack antigen presenting cells

what is the function of helper T cells?

stimulate activation of B and T cells

what is the function of regulatory T cells?

moderate the immune response

what is the function of memory T cells?

produced during the initial response to an antigen, producing a rapid and strong immune response to later presentations of the same antigen

what are MHC proteins?

glycoproteins on the plasma membranes that antigens bind to

what is the function of MHC proteins?

when bound to antigens, they can activate T cells

where are class I MHC proteins found?

plasma membrane of all nucleated cells

where are class II MHC proteins found?

plasma membrane of antigen presenting cells and lymphocytes

what do inactive T cells contain?

receptors that bind either class I or class II MHC proteins and specific antigens

what happens if a T cell recognizes its specific antigen on the MHC protein?

it will bind to the MHC protein

where are cluster of differentiation markers found?

on the membrane of T cells

what do cluster of differentiation markers determine?

if the T cell will bind to class I or class II MHC proteins

what are the cells that have class II MHC proteins?

antigen presenting cells and lymphocytes

what are the 3 types of antigen presenting cells?

phagocytes, dendritic cells, and B cells

which cells display CD8 markers on their plasma membrane?

cytotoxic T cells and regulatory T cells

what do CD8 T cells bind to?

class I MHC proteins

which cells display CD4 markers on their plasma membrane?

helper T cells

what do CD4 T cells bind to?

class II MHC proteins

what happens once T cells are activated?

they undergo mitosis and produce clones of identical cells

what do cytotoxic T cells release to destroy infected cells?

perforins, cytokines, lymphotoxins

what do perforins do?

form pores on the plasma membrane of the target cell

what do cytokines do to kill cells?

activate genes for apoptosis

what does lymphotoxin do?

kills target cell

what do memory T cells differentiate into when re-exposed to an antigen?

cytotoxic T cells

what do helper T cells secrete?

cytokines that stimulate humoral and cellular immunity

what is the role of cytokines secreted by helper T cells in B and T cell activation?

• stimulates T cell division that produce memory T cells

• speed maturation of cytotoxic T cells

• enhance nonspecific defenses by attracting macrophages to affected area

• attract and stimulate cytotoxic T cells

• promote activation of B cells

what are the steps in B cell sensitization?

1. antigens bind to class II MHC proteins and appear on the plasma membrane of the B cell

1. once the B cell exhibits the antigen on the MHC proteins, it is sensitized and ready to be activated