these vessels carry blood away from the heart & toward the tissues; the heart's ventricles pump blood into these
these vessels are small subdivisions of the arteries; they carry blood into the capillaries
these are tiny, thin-walled vessels that allow for exchanges between systems; exchanges occur between the blood & body cells/ between the blood & air in the lung; these connect arterioles & venules
these are small vessels that receive blood from capillaries & begin its transport back toward the heart
these are vessels formed by the merger of venules; they continue blood's transport until it is returned to the heart
this circuit delivers blood to the lungs, where some carbon dioxide is eliminated & oxygen is replenished
1. the pulmonary trunk & its arterial branches, carry blood low in oxygen from the right ventricle to the lungs
2. the capillaries in the lungs, through which gases, nutrients, & wastes are exchanged
3. the pulmonary veins carry freshly oxgenated blood back to the left atrium
what does the pulmonary circuit do?
pulmonary arteries carry blood that is low in oxygen content, & pulmonary veins carry blood that is high in oxygen content; in contrast the systemic arteries carry highly oxygenated blood, & the systemic veins carry blood that is low in oxygen
what is the difference of the vessels in the systemic & pulmonary circuit?
this circuit serves the rest of body; these vessels supply nutrients & oxygen to all tissues & carry waste materials away from the tissues for disposal
1. the aorta receives freshly oxgenated blood from the left ventricle & then branches into the systemic arteries carrying blood to the tissues
2. the systemic capillaries are the blood vessels through which materials are exchanged
3. the systemic veins carry blood in oxygen back toward the heart; the venous blood flows into the right atrium of the heart through the superior vena cava & inferior vena cava
What does the systemic circuit do?
endothelium- inner tunic, smooth muscle- middle tunic & connective tissue- outer tunic
what are the 3 layers of the artery?
thick walls, strong enough to receive blood pumped under pressure from heart's ventricle; elastic tissue between layers of arterial wall allows these vessels to stretch when receiving blood & then return to their original size
what is the vessel structure of arteries?
endothelium- inner tunic
inner most membrane; forms a smooth surface over which the blood flows easily; simple flat epithelial cells
these have thinner walls than arteries, little elastic connective tissue, but relatively more smooth muscle
these connect arterioles & venules; these have the thinnest walls of any vessels: one cell layer; transparent walls that are a continuation of smooth endothelium that lines the arteries
allows for exchange between the blood & body cells & between the lung tissue & outside air
why are the capillary walls so thin?
what on the capillary is the most important center of activity for the entire circulation system?
these are the smallest veins; formed by the union of capillaries; their walls are only slightly thicker than those of capillaries; as these merge to form veins, the smooth muscle in the vessel walls become thicker & these begin to aquire the additional layers found in larger vessels
this vessel has the same 3 layers as arteries- endothelium- inner tunic, smooth muscle- middle tunic & connective tissue- outer tunic
the veins & arteries have the same 3 layers; however the middle smooth muscle tunic is relatively thin in veins; the vein wall is much thinner than the wall of artery; veins have less elastic tissue between the layers, so they can expand easily & carry blood under much lower pressure; because of their thinner walls, veins collapse easily; most veins have one-way valves that permit blood to flow in only 1 direction: toward the heart, capillaries don't have valves
what is the difference in vessel structure of veins & arteries?
pulmonary circuit- carries blood from the heart to the lungs to pick up oxygen & then back to the heart; the systemic circuit carries blood to & from all remaining tissues in the body
what are the 2 blood circuits & what areas does each serve?
smooth muscle makes the middle tunic; it is involuntary muscle controlled by autonomic nervous system
what type of tissue makes up the middle tunic of arteries & veins, & how is this tissue controlled?
this vessel receives blood from the left ventricle, ascends from the heart, & then arches back to travel downward through the body, branching to all organs
1. ascending aorta
2. aortic arch
3. thoractic aorta
4. abdominal aorta
what are the 4 parts of the aorta?
this part of aorta lies just anterior to the vertebral column posterior to the heart in the mediastinium
this part of aorta is the longest section of the aorta, beginning at the diaphragm & spanning the abdominal cavity
1. brachiocephalic artery, divides into right subclavian artery & right common carotid artery
2. the left common carotid artery
3. left subclavian artery
what are the branches of the ascending aorta& arch?
this is a short vessel that supplies the arm & head on the right side (unpaired)
right subclavian artery
after extending upward about 5 cm, the brachiocephalic divides into this, which extends under the right clavicle (collar bone) supplies the right upper (arm)
left common carotid artery
this extends upward from the highest part of the aortic arch; supplies the left side of the neck & head
left subclavian artery
this extends under the left clavicle & supplies the left upper extremity; this is the aortic arch's last branch
1. celiac trunk, subdivides into 3 branches: left gastric artery, splenic artery, & hepatic artery
2. superior mesenteric artery
3. inferior mesenteric artery
what are the unpaired branches of the descending aorta?
1. superior & inferior phrenic arteries
2. renal arteries
3. suprarenal arteries
3. gonadal arteries (ovarian & testicular arteries)
4. 4 pair of lumbar arteries
what are the paired lateral branches of the descending aorta?
this is a short artery, about 1.25 cm long, that subdivides into 3 branches: left gastric artery, splenic artery & hepatic artery
superior mesenteric artery
this is the largest of the these branches, carries blood to most of the small intestine & to the 1st half of large intestine
inferior mesenteric artery
this is located below the superior mesenteric artery & near the end of the abdominal aorta, supplies the 2nd half of the large intestine
the largest in this group of abdominal aorta paired lateral branches, carry blood to the kidneys
the ovarian arteries in females & testicular arteries in males- supply the sex glands
the abdominal aorta divides into 2 common iliac arteries, each subdivides into internal & external iliac artery; branches in the thigh & then becomes popliteal artery, which subdivides into anterior & posterior tibial arteries, the anterior tibial artery terminates as the dorsalis pedis at the foot; posterior tibial artery gives rise to fibular artery in leg
what are the iliac arteries & their subdivisions?
common iliac artery
these vessels are 5 cm long, extend into the pelvis, where each subdivides into an internal & external iliac artery
internal iliac artery
these vessels send branches to the pelvic organs, includng the urinary bladder, the rectum & reproductive organs other than the gonads (reproductive organs)
external iliac artery
each of these vessels continues into the thigh as femoral artery, this vessel gives rise to branches in the thigh & then becomes the popliteal artery subdivides below the knee, subdivisions include posterior & anterior tibial arteries & dorsalispedis which supply leg & foot
this artery branches off the femoral artery; subdivides below the knee into the anterior & posterior tibial arteries
external & internal carotid arteries, subclavian artery, vertebral artery, axillary artery, brachial artery, radial artery & ulnar artery
what are the arteries that branch to the arm & head?
external & internal carotid arteries
each common carotid artery travels along the trachea enclosed in a sheath with the internal jugular vein & vagus nerve; just anterior to the angle of the mandible (lower jaw) it branches into these
internal carotid artery
this artery travels into the head & branches to supply the eye, the anterior portion of the brain, the other structures in the cranium
external carotid artery
this artery branches to the thyroid gland & to other structures in the head & upper part of the neck
this artery supplies blood to the arm & hand; this changes names as it travels through the arm & branches to the forearm & hand; it 1st becomes axillary artery, then brachial artery, then radial artery, then ulnar artery
the 1st branch of subclavian artery, which passes through the transverse processes of the 1st cervical vertebrae & supplies blood to the posterior brain
the 2nd name change of subclavian artery, the longest part of the vessel, is in the arm proper; this subdivides into branches near the elbow: radial & ulnar arteries
this artery branches off the brachial artery; continues down the thumb side of the forearm & wrist
this artery branches off the brachial artery; extends along the medial or little finger side into the hand
a communication between 2 vessels, by means of these, blood reaches vital organs by more than 1 route
circle of Willis (cerebral arterial circle), superficial palmar arch, mesenteric arches, & deep plantar arch
what are the 4 different types of anastomoses?
circle of Willis (cerebral arterial circle)
this receives blood from the 2 internal carotid arteries & from the basilar artery, which is formed by the union of 2 vertebral arteries; this arterial circle lies just under the brain's center & sends branches to the cerebrum & other parts of brain
superficial palmar arch
this arch is formed by the union of the radial & ulnar arteries in the hand; it sends branches to the hand & fingers
this arch is made up of communications between branches of the vessels that supply blood to the intestinal tract
this arch is formed by the union of the lateral plantar artery, which travels across the bases of the metatarsal bones, & the dorsalis pedis
ascending aorta, aortic arch, thoracic aorta, & abdominal; the thoracic & abdominal make up the descending aorta
what are the subdivisions of the aorta, the largest artery?
veins in the back of the hand & front of the elbow: cephalic vein, basilic vein, median cubital veins & saphenous veins
where are the superficial veins?
for drawing blood for testing purposes (venipunture) & (IV) intravenous injections
the veins at the elbow: cephalic, basilic & median cubital veins are used for what purpose?
veins of lower extremities, which are the body's longest veins; begins in the foot & extends up the medial side of leg, the knee, & thigh; it finally empties into the femoral vein near the groin
what veins tend to parallel arteries & usually have the same names as corresponding arteries?
the veins of the head, neck, upper extremities, & chest
what veins drain into the superior vena cava?
the SVC is formed by the union of the right & left brachiocephalic veins, which drain the head, neck, & upper extremities; the unpaired azygos vein drains the veins of the chest wall & empties into the superior vena cava
what are the tributaries of the superior vena cava?
the inferior vena cava
this is much longer than the superior vena cava, returns blood from the areas below the diaphragm; drainage in this is more complicated , divided into 2 parts
1. unpaired veins that drain the spleen & parts of the digestive tract empty into hepatic portal veins (enables blood to circulate through the liver before returning to the heart)
2. iliac, lumbar, ovarian & testicular, renal & suprarenal, & hepatic veins (from the liver) these vessels empty into IVC
what are the 2 groups of veins that empty in the IVC?
this is a large channel that drains blood low in oxygen, but does not have a vein's usual tubular structure
this is an example of a venous sinus that receives most of the blood from the heart wall; it lies between the left atrium & left ventricle on heart's posterior surface & empties directly into the right atrium, along with the 2 venae cavae
a portal system
blood circulates through a 2nd capillary bed, usually in a 2nd organ, before it returns to the heart; it's kinda like a detour pathway of venous return that transport materials directly from 1 organ to another
hepatic portal system
this system carries blood from the abdominal organs to the liver to be processed before it returns to the heart; it includes the veins that drain blood from capillaries in the spleen, stomach, pancreas, & intestine; instead of emptying blood directly in IVC its delivered thru the hepatic portal vein to the liver; the portal vein's largest tributary is the superior mesenteric vein which drains blood from the proximal portion of the intestine
is to transport blood from the digestive organs & spleen to liver sinusoids so that the liver cells can carry their functions (when food is digested most of end products are absorbed from sm intestine into blood stream & transported to the liver by portal system; in the liver these nutrients are processed, stored, & released as needed into general circulation)
what is the purpose of the hepatic portal system?
superficial veins are near the surface; deep veins are closer to the interior & generally parallel the arteries
what is the difference between superficial & deep veins?
the superior vena cava & inferior vena cava drain the systemic circuit & empty into right atrium
What 2 large veins drain the systemic blood vessels & empty into the right atrium?
interstitial fluid or tissue fluid
all living cells are immersed in this slightly salty liquid; this fluid serves as "middleman" between the capillary membrane & neighboring cells
this is the main process by which substances move between the cells & the capillary blood; the movement of a substance from an area where it is in higher concentration to an area where it is in lower concentration; does not require transporters or cellular energy
this is the force that filters or pushes water & dissolved materials out of the capillary into the tissue fluid
fluid is drawn back into the capillary by this pressure, the "pulling force" of substances dissolved & suspended in the blood; this pressure is maintained by plasma proteins (mainly albumin), which are too large in molecular size to go through the capillary wall
by changing the size of the blood vessels supplying that organ: vasodilation- allows more blood to area & vasoconsriction- decrease in blood flow
how can the volume of blood flowing to a particular organ be regulated?
these activities result from the contraction or relaxation of smooth muscle in the walls of blood vessels, mainly the arterioles
in the medulla of the brain
where is the vasomotor center, which regulates vasomotor activities, sending its messages through the autonomic nervous system?
this is smooth muscle that encircles the entrance to the capillary & regulates blood flow, widens to allow more blood to enter when tissues need more oxygen
contraction of skeletal muscles- they compress the veins & squeeze blood forward, valves in the veins- prevent back flow & keep blood flowing toward the heart, & breathing- pressures changes in the abdominal & thoracic cavities help with bloods return to the heart
what mechanisms help to get blood returned to the heart, in the venous system?
1.size of person- pulse is somewhat faster in small people than in large & in women than in men
2. age of person- in a newborn infant may be 120 to 140 beats/min as child grows the rate becomes slower
3. muscular activity influences pulse rate- during sleep pulse may slow down to 60 beats/ min- during strenuous exercise the rate may go up to over 100 beats/min
4. emotional disturbances- may increase the pulse rate
5. temperature- pulse rate increases with increased temperature as in infection
6. thyroid hormone- excessive secretion of thyroid hormone may cause a rapid pulse
what are 6 factors that influence the pulse rate?
total blood volume, cardiac output, resistance to blood flow, & blood vessel compliance & elasticity
what factors affect blood pressure?
total blood volume
this refers to the total amount of blood that is in the vascular system at a given time; loss of bld volume by hemorrhage will lower bld pressure; increase in bld volume will increase pressure within the vessels thereby increase CO by increasing venous return
cardiac output (CO)
the volume of blood pumped out of each ventricle in 1 minute; is the product of 2 factors- heart rate & stroke volume
the number of times the heart beats each minute (basic heart rate is set by SA node but can be infleunced by autonomic nervous system, hormones, & other substances circulating in the blood)
the volume of blood ejected from the ventricle with each beat; sympathetic nervous system can stimulate more forceful heart contractions to increase blood ejection
blood vessel diameter: a narrow vessel offers more resistance to blood flow than a wider vessel, blood viscosity or thickness: increased blood thickness will increase blood pressure, & blood vessel length: a longer vessel offers more resistance to blood than a shorter vessel
what factors affects the resistance to blood flow?
the carotid arteries & the aorta have these in their walls to detect changes in blood pressure
the maximum pressure that develops in the arteries after heart muscle contraction ( normal = 120)
the lowest pressure measured in the arteries after relaxation of heart muscle (normal= 80)
sphygmomanometer (blood pressure cuff or blood pressure apparatus)
the instrument used to measure blood pressure
as systolic pressure 1st, then diastolic pressure, separated by a slash, such as 120/80
how is blood pressure recorded?
this enzyme produced in the kidney, appears to play a role in the severity of essential hypertension
1. weaken vessels & lead to saclike bulges (aneurysms) in vessel walls that are likely to rupture
2. stress the heart by causing it to work harder to pump blood into arterial system; in response to this greater effort, the heart enlarges, but eventually weakens & becomes less efficient
3. stress the kidneys & damage renal vessels
4. damage the lining of vessels predisposing to atherosclerosis
hypertension can cause these 4 things
1. diuretic drugs that promote water loss through the kidneys
2. drugs that limit production of renin or block its action
3. drugs that relax blood vessels, including adrenergic blockers & calcium channel blockers
treatment of hypertension
this begins with microscopic damage to the arterial endothelium caused by direct contact with LDL (the
"bad" cholestrol), oxidizing chemicals; streaky areas of yellow, fatlike material (plaque) appear in vessel, it accumulates, separates the wall's muscle & elastic tissue layers; arterial wall bulges into vessel's lumen & interferes with blood flow. Platelets can aggregate at the site of plaque formation, leading to development of blood clot (thrombus) & partial or complete obstruction of the vessel
1.leg cramps, pain, & sudden lameness while walking caused by insufficient blood supply to lower extremities resulting from arterial damage
2. headaches, dizziness & mental disorders may be result of cerebral artery sclerosis
3. hypertension may result from a decrease in lumen size within many arteries throughout body
4. palpitations, dyspnea (difficulty breathing), paleness, & weakness
5. an increase in amount of urine with appearance of albumin
6. ulceration & tissue necrosis (death)
signs & symptoms of arterial degeneration
this is a bulging sac in a blood vessel's wall caused by a localized weakness in that part of the vessel; enlarges & may rupture (aorta & vessels in brain are common sites)
1. facial artery
2. temporal artery
3. common carotid artery
4. subclavian artery
5. brachial artery
6. femoral artery
what are the 6 pressure points in body that can stop or slow bleeding?
facial artery (1 inch anterior to lower jaw's angle)
what artery may be pressed against the lower jaw for hemorrhage around the nose, mouth, & cheek?
what artery may be pressed against the side of the skull just anterior to the ear to stop hemorrhage on the side of face & around ear?
common carotid artery
what artery in the neck may be pressed back against the spinal column for bleeding in the neck & head?
what artery may be pressed against the first rib by a downward push with the thumb to stop bleeding from the shoulder & arm?
what artery may be pressed against the humerus (arm bone) by a push inward along the natural groove between the arm's 2 large muscles; this stops hand, wrist & forearm hemorrhage?
what artery (in the groin) may be pressed to avoid serious hemorrhage of lower extremities
refers to a life-threatening condition in which there is inadequate blood flow to the body tissues
cardiogenic shock, septic shock, hypovolemic shock, & anaphylactic shock
What are 4 important types of shock?
sometimes called pump failure, is often a complication of heart muscle damage, as occurs in myocardial infarction
is second only to cardiogenic shock as a cause of shock death; it is usually the result of an overwhelming bacterial infection
this type of shock is caused by a decrease in the volume of circulating blood & may follow severe hemorrhage or burns
this is a severe allergic reaction to foreign substances to which the person has been sensitized
according to its severity- mild shock & severe shock
when the cause is not known how is shock classified?
in this shock, regulatory mechanisms relieve the circulatory deficit; signs are often subtle changes in heart rate & blood pressure; this may develop into a serve, life-threatening circulatory failure
this shock is characterized by poor circulation, which causes further damage & deepening of the shock; late shock symptoms include clammy skin, anxiety, low blood pressure, rapid pulse, & rapid, shallow breathing
thrombosis (deep vein thrombosis)
formation of a blood clot in a vein; most commonly in the deep veins of calf muscle
skeletal muscle contractions generate pressure thereby forcing lymph to move
how is lymph returned to the circulatory system?
lymphocytes & phagocytes
what specialized cells in the lymphatic system destroy microorganisms such as bacteria carried by the lymph fluid?
thin walls & valves in the larger vessels
what are the features of the vessels of the lymphatic system?
it picks up excess fluid & protein left behind in the tissues by lymphatic capillaries which are located in the body tissues
how does the lymphatic system control fluid balance?
a clear fluid similar in composition to interstitial fluid; this is formed from the components of blood plasma, differs from plasma in that it has much less protein
it is an important component of the immune system, which fights infection; lymphocytes are part of the wbc's & can live & multiply in the lymphatic system & attack & destroy foreign organisms; lymphoid tissue is scattered thruout the body & they filter out pathogens (organisms that cause disease, foreign matter, & cellular debris)
how does the lymphatic system protect the body?
many digested fats too large to enter the blood capillaries are absorbed into lymphatic capillaries called lacteals; these fats are added to the blood when lymph joins the bloodstream
how does the lymphatic system help with the absorption of fats?
this is a 1 way system that begins in the tissues & ends when the lymph joins the blood; it is not a complete circuit
the lymphatic capillaries
the walls of these capillaries are made up of 1 layer of flattened (squamous) epithelial cells; this thin layer also called endothelium, allows for easy passage of soluble materials & water through capillary wall; they are more permeable allowing for easier entrance of relatively large protein molecules; proteins can't move backward due to 1 way valves that block their return. Located in small intestine's lining, absorbed digested fats are called lacteals & these lacteals transport fat through the lymphatic vessels until the lymph is added to the blood
these vessels are thin walled & delicate, have a beaded appearance because of where the valves are located, valves prevent backflow of fluid with valves; include superficial & deep sets; named according to their location; carry lymph away from the regional nodes which eventually drain into 1 or 2 terminal vessels; the right lymphatic duct or the thoracic duct; both empty into the blood stream
right lymphatic duct
this is short & receives only the lymph that comes from the body's superior right quadrant (right side of head, neck, and thorax & right upper extremity) empties into the right subclavian vein near the heart
thoracic duct or left lymphatic duct
this is larger than right lymphatic duct; it receives lymph from all parts of the body except those superior to the diaphragm on the right side; duct's 1st part is enlarged to form a cistern or temporary storage pouch called the cisternachchyli, chyle is the milky fluid that drains from the intestinal lacteals & it is formed by fat globules & lymph; chyle passes through intestinal lymphatic vessels then the lymph nodes of the mesentery, finally entering cisterna chyli as well as lymph from below the diaphragm also empties in the cisterna chyli, this duct then carries the lymph into the blood stream
movement of lymph
this happens by segments of lymphatic vessels located between the valves contract, propelling lymph forward; contraction rate is related to fluid volume in vessel- the more fluid, the more rapid contraction. It is also moved when skeletal muscles contract during movement, they compress lymphatic vessels & drive lymph forward. Changes in pressures within the abdominal & thoracic cavities during breathing aid this movement
these are designed to filter the lymph as it travels through the lymphatic vessels, also sites where lymphocytes of the immune system multiply & work to combat foreign organisms. These are small, rounded masses, that are seldom isolated
an outer cortex & an inner medulla; each of these regions are subdivided into lymph-filled sinuses & cords of lymphatic tissue
what 2 regions are lymph nodes divided into?
this is distributed throughout the body & makes up the lymphatic system's specialized organs
cervical nodes, axillary nodes, trachebrachial nodes, mesenteric nodes, & inguinal nodes
what are the main groups of lymph nodes?
these are located in the neck in deep & superficial groups, drain various parts of the head & neck
these nodes are located in the axillae (armpits), become enlarged after infections of upper ext & breasts; cancer cells from the the breast metastasize to here
these nodes are located in the groin region, receive lymph from lower ext ext gentital organs; when enlarged are called buboes
this is an organ containing lymphoid tissue that filters blood; it is located in the superior left hypochondriac region of the abdomen, high up under the dome of the diaphragm, & is protected by the lower part of rib cage; contains involuntary muscle which enables the capsule to contract & withstand some swelling; unusual large blood supply; filled with soft pulp that filters blood; it harbors phagocytes & lymphocytes
because it contains prominent masses of lymphoid tissue
why is the spleen classified as a lymphatic organ?
1. cleanes the blood of impurities & cellular debris
2. destroys worn out RBC's
3. producing RBC's before birth
4. serves as a reservoir for blood which can be returned to the bloodstream in case of hemorrage
What are the 4 other functions of the spleen?
this organ is located in the superior thorax deep to the sternum, plays a role in immune system development during fetal life & infancy; the hormone thymosin promotes lymphocyte growth & lymphoid tissue activity throughout the body; T cells, must mature here before they can perform their functions in immune system; most active during early life after puberty tissue undergoes changes shrinking in size, by adulthood it has been replaced by connective tissue & fat
these are unencapsulated masses of lymphoid tissue located in the vicinity of the pharynx (throat) where they remove contaminants from materials that are inhaled or swallowed; lymphocytes attack pathogens trapped in the groves of these
1. palatine tonsils- are oval bodies located at each side of the soft palate
2. pharyngeal tonsil- is a single tonsil, commonly referred to as adenoids, located behind the nose on the posterior wall of the upper pharynx
3. lingual tonsils- little mounds of lymphoid tissue at the posterior tongue
what are the 3 types of tonsils & where are they located?
this is a fingerlike tube of lymphoid tissue, measuring about 8 cm; it is attached, or "appended" to the 1st portion of the large intestine
MALT or mucosal associated lymphoid tissue
this prevents microorganisms from invading deeper tissues; this is recognized as 1st barrier against invading microorganisms
these are part of the MALT system, consist of clusters of lymphoid nodules located in the mucous membranes lining of the small intestine
inflammation of the lymphatic vessels; begins in the region of an infected or neglected injury & can been seen as red streaks extending along an extremity, this is a sign of bacteria having spread into the lymphatic system & if lymph nodes can't stop the infection pathogens enter the bloodstream causing septicemia (blood poisoning); strep is usually the culprit
inflammation of lymph nodes; nodes become enlarged & tender, this condition reflects the body's attempt to combat an infection
edema (tissue swelling due to excess fluid) due to obstruction of lymph flow; an early sign for HIV the virus that causes AIDS; enlargement of cervical lymph nodes is an early sign for infectious mononucleosis (mono-"kissing disease")
infection of lymphatic vessels, malignant growth that obstructs lymph flow, loss of lymphatic vessels & nodes as a result of injury or surgery
what are some of the causes of lymphedema?
because the lymphatic system's filtering activity is diminished
why are areas affected by lymphedema more prone to infection?
this is enlargement of the lower extremities resulting from lymphatic vessel blockage by small worms called filariae. These tiny parasites, carried by insects such as flies & mosquitoes, invade the tissues as embryos or immature forms; they then grow in the lymph channels & obstruct lymphatic flow. Swelling of legs or, sometimes happens in men, the scotum, may be so great that victim becomes incapacitated= no cure is known
enlargement of the spleen, accompanies certain acute infectious diseases, including infectious mononucleosis, scarlet fever, typhus fever, typhoid fever, & syphilis
any tumor, benign or malignant, that occurs in lymphoid tissue; 2 examples are Hodgkin lymphoma & Non-Hodgkin lymphoma
Hodgkin lymphoma disease
a chronic malignant disease of lymphoid tissue especially the lymph nodes; seen in the early 20's of both men & women; after 50 more common in men. Cause unknown, but may involve viral infection; painless, enlargement of a lymph node or close group of nodes, often in neck but also axillary, thorax & groin & can spread throughout lymphatic system & eventually to other systems if not treated. Early signs are weight loss, fever, night sweats, fatique, anemis & decline in immune defenses. A clear sign of disease is the presence of Reed-Sternberg cells in lymph node biopsy. Treatment is chemo & radiotherapy
this is more common than Hodgkin; seen primarily in older adults & patients with deficient immune system (AIDS) Signs are enlargement of lymph nodes (lymphadenopathy) esp. cervical region (early sign indicator); more wide spread than Hodgkin thru the lymphatic system & spreads readily to other tissues such as liver. There is NO Reed-Sternberg cells on biopsy; current cure rate with chemo & radiation is 50%
which of the following is NOT a lymphoid tissue?
a widely distributed system consisting of all the cells able to ingest bacteria or colloidal particles etc, except for certain white blood cells
which vessel returns lymph from the lower extremities to to the cardiovascular system?
the quality of being unaffected by something; all of the defenses that protect us against disease
HIV (Human immunodeficincy virus)
the virus that causes AIDS (acquired immunodeficiency syndrome), attacks a certain type of T cell (T-lymphocyte), which has surface receptors for the virus
respiratory tract, digestive tract, tubes that open into the urinary & reproductive systems, a break in skin, & mucous membrane
what are 5 portals of entry
1. invasive power, or "aggressiveness"
2. organism's ability to produce toxin (poisons) that damage the body
what are the 2 aspects of virulence?
number of pathogens that invade the body, also is a determining factor in whether or not an infection develops
pathogen access to preferred body tissues, portal of entry, virulence, dose, & an individual's predisposition to infection
what are some factors that influence the occurrence of infection?
immunity that is inborn, or innate, that is, inherited along with all of a person's other characteristics; they include barriers & certain internal cellular & metabolic responses that protect against;effective against any harmful agent
1st line of defense
chemical & mechanical barriers=mucous membranes, body secretions & certain reflexes
skin serves for this type of barrier as long as it remains in intact, also mucous membranes that line the passageways leading into the body act as barriers, trapping foreign material in their sticky secretions. The cilia in membranes in upper respiratory tract help to sweep impurities out of body
body secretions, such as tears, perspiration, & saliva, wash away microorganisms & may contain acids, enzymes& other chemicals that destroy invaders. Digestive juices destroy many ingested bacteria & their toxins
reflexes that aid in the removal of pathogens
sneezing & coughing, remove foreign matter, including microorganisms, from the upper respiratory tract; also vomiting & diarrhea are ways in which ingested toxins & bacteria may be expelled
part of the 2nd line of defense against invaders of the body; white blood cells take in & destroy foreign material= neutrophils (granular leukocytes) & macrophages (derived from the monocyte, agranular) are the main phagocytic white cells; both neutrophils & macrophages travel to the site of the infection & some of the macrophages remain fixed to fight infection & remove debris
natural killer cells
type of lymphocyte different from those in specific immunity; recognize body cells with abnormal membranes such as tumor cells & cells infected with virus & destroys them on contact; found in the lymph nodes, spleen, bone marrow & blood; these destroy abnormal cells by secreting a protein that breaks down cell membrane
this is a nonspecific defensive response to a tissue damaging irritant, often results from irritation caused by infection
this is a mixture of leukocytes & fluid which contributes to swelling & puts pressure on nerve endings adding to the pain of inflammation
an increased in body temperature above normal range (98.6); presence of phagocytes exposed to infecting organisms releases substances that raises body temperature;boosts the immune system by stimulating phagocytes, increases metabolism & decreases certain disease organism's ability to multiply
this is a substance that prevents nearby cells from producing more virus; first found in cells infected with influenza virus; interferes with multiplication & spread of the virus
the destruction of foreign cells sometimes requires the activity of a group of nonspecific proteins in the blood; it complements (assist with) immune reactions
bind to foreign cells to help phagocytes recognize & engulf them, destroy cells by forming complexes that punch holes in plasma membranes, promote inflammation by increasing capillary permeability, & attract phagocytes to an area of inflammation
what are the 4 complement actions?
this is an individual's power to resist or overcome the effects of a particular disease agent
final line of defense- any foreign substance that induces a immune response (word is formed from antibody + gen, because this generates antibody production); most are large proteins. normally, only nonself ---------- stimulate an immune response & are found on surfaces of pathogenic organisms, transfused blood cells, transplanted tissues, cancerous cells, & pollens, in toxins, & in foods;
stimulate the activity of certain lymphocytes classified as T or B cells
what is a critical feature of an antigen?
cytotoxic T cells (Tc), helper T cells (Th), regulatory T cells (Treg), & memory T cells
what are 4 types of T cells?
cytotoxic T cells (Tc)
these T cells destroy certain abnormal cells directly, they recognize cells infected with viruses or other intracellular pathogens, cancer cells, & foreign antigens present in transplanted tissue. They are able to form pores in the plasma membranes of these cells & insert enzymes that destroy the cell; they also produce substances that cause the cells to "self -destruct" by apoptosis
helper T cells (Th)
these T cells are essential to the immune response through the release of substances known as interleukins; these substances stimulate the production of cytotoxic T cells as well as B cells & macrophages
the helper T cells, one of which is infected & destroyed by AIDS virus (HIV), The HIV-targeted T cells have what special surface receptor to which the virus attaches?
regulatory T cells (Treg)
these T cells suppress the immune response in order to prevent overactivity; they may inhibit or destroy active lymphocytes
memory T cells
these T cells remember an antigen & start a rapid response if that antigen is contacted again
antigen-presenting cells APC's
most important of these cells are macrophages & dendritic cells derived from monocytes; act as process center for foreign antigens, 1st it ingests the foreign material enclosing it in a vesicle, this vesicle then merges with a lysosome filled with digestive enzymes that break down the organism, these cells then insert fragments of the foreign antigen into its plasma membrane advertising them to the T cells, they display the foreign antigen in combination with antigens that a T helper cell can recognize as belonging to the "self"
take in & digest foreign antigens, they then display fragments of the antigen in their plasma membrane along with self (MHC) antigens that a T cell can recognize
what is the role of APC's in immunity?
B cells (B lymphocytes)
these are the 2nd main class of lymphocytes active in immunity, these cells mature in the red bone marrow before becoming active in blood ; function in immunity by producing Y-shaped proteins called antibodies ; these cells have surface receptors that bind with a specific type of antigen, exposure to the antigen stimulate the cells to multiply rapidly & produce large # of clones or plasma cells
antibody-mediated defense; resides ultimately in the B lymphocytes and is mediated by the antibodies produced by B cells
Pertussis toxoid, Haemophilus influenza type B (HIB), & Pneumococcal vaccine (PCV)
3 examples of bacterial vaccines
Haemophilus influenza type B (HIB)
vaccine prevents preschool children from getting life threatening meningitis, can also cause pneunomia & recurrent ear infections in young children can be given 2,4 or 2,4,6mos
Pneumococcal vaccine (PCV)
protects against infection with pneumococcus an organism that causes pneumonia & meningitis; schedule: 2,4,6, & 12-15mos
IPV or OPV, IPV, MMR, Hepatitus B, Varcellia vaccine, influenza, rotavirus, human Papilloma virus (HPV), rabies vaccine
8 examples for viral vaccines
infants receive 1 shot just after birth & the other 2 before 18 mos; schedule: birth, 1-2 mos, 6-18mos
Varcellia vaccine (chickenpox)
schedule: 12 mos & 4-6 yrs; adults age 60 yrs & older receive the live virus shingles vaccine
causes a highly contagious GI infection among babies & toddlers; s/s: vomiting & diarrhea lead to life threatening dehydration; schedule: 2,4 & 6 mos
Human Papilloma virus (HPV)
cause sexually transmitted genital warts in both men & women & assoc with almost all cervical cancer in women; schedule: girls age 11-12 yr & 13-26 yr who have not been vaccinated
should be given if person has an invasion of the organism caused by bite of wild animals such as raccoons, bats, foxes, & skunks; no cure for rabies it is fatal in nearly all cases
immune serum or antiserum
Is a serum from an animal or man, which is immunized against a specific disease.
An example of this is the rabies immune globulin.
natural immunity develops from contact with a disease or passage of antibodies through the placenta or mother's milk. Artificial acquired immunity develops from immunization with a vaccine of an immune serum
what is the difference between natural & artificial acquired immunity?
active acquired immunity develops from contact with a disease organism either naturally or in a vaccine. Passive acquired immunity is obtained by antibodies from an outside source, either through the placenta & mother's milk or as an immune serum
what is the difference between the active & passive forms of acquired immunity?
this is a cancer of the blood-forming cells in bone marrow, mainly the plasma cells that produce antibodies they produce excess of a particular antibody but they are not effective; high blood levels of ca++ & proteins secreted by the plasma cells often lead to kidney failure; treated with chemo, a new approach treating with hi doses of chemo & bone marrow transplant
is the grafting to a recipient of an organ or tissue from an animal or other human to replace an injured body part
this is an organism's natural tendency to destroy foreign substances including tissues from another person or any other animal
helper T cells
these cells release interleukins, which stimulate other cells ti join the immune response
memory T cells
these cells remember an antigen & start a rapid response if the antigen is contacted again
which of the following is part of the internal nonspecific response to infection?
which of the following do damage cells release?
(a) T cell
which cell matures in the thymus?
a. T cell
b. B cell
c. plasma cell
d. natural killer cell