Question | Answer |
The growth of new blood vessels. Vital process in the fetus and in postnatal growth. | Angiogenesis |
Malignant tumors secrete proteins called ________ that stimulate blood vessel growth to nature the tumor cells. | Tumor angiogenesis factors (TAFs) |
forces involved in circulating blood | Hemodynamics |
________ form a closed system that carry blood away from the heart, transport it to the tissues of the body, and then return it to the heart. | Blood vessels |
Carry blood away from the heart to the tissues. | Arteries |
Are small arteries that supply capillaries. | Arterioles |
Are the site of exchange between the blood and
tissues. | Capillaries |
Connect blood from capillaries and return blood to larger
veins. | Venules |
Take blood from the tissues back to the heart. | Veins |
Are small blood vessels that supply blood to the
cells of the walls of large arteries and veins. | Vaso vasorum |
The wall of an artery have three major layers | Tunica interna, Tunica media, Tunica externa |
Simple squamous epithelium called endothelium
basement membrane
internal elastic lamina | Tunica interna (intima) |
circular smooth muscle & elastic fibers | Tunica media |
elastic & collagen fibers | Tunica externa |
The functional properties of arteries are ______ and _______. | elasticity; contractility |
allows arteries to receive blood under great pressure from the contraction of the ventricles and to send it on through the system | Elasticity |
allows arteries to increase or decrease lumen size. This helps propel blood forward and to limit bleeding from wounds. | Contractility |
Vascular smooth muscle is innervated by _________. | sympathetic nervous system |
increase in sympathetic stimulation causes muscle contraction.
decreases diameter of vessel | Vasoconstriction |
injury to artery or arteriole causes muscle contraction
reducing blood loss | Vasospasm |
decrease in stimulation or presence of certain
chemicals causes vasodilation.
increases diameter of vessel
nitric oxide, K+, H+ and lactic acid cause vasodilation | relaxation of smooth muscle layer |
Large arteries with more elastic fibers and less smooth muscle are called _______ and are able to receive blood under pressure and propel it onward. Function as a pressure reservoir. | elastic arteries |
Elastic Arteries are also called ______ because they conduct blood from the heart to medium sized muscular arteries. | conducting arteries |
Medium-sized arteries with more muscle than elastic fibers in tunica media.These arteries are capable of greater vasoconstriction and vasodilation to adjust rate of flow. Walls are relatively thick. | Muscular Arteries |
_____ are very small, almost microscopic, arteries that deliver blood to capillaries. The greatest resistance to blood flow. | Arterioles |
Through vasoconstriction and vasodilation arterioles assume a key role in regulating blood flow from arteries into capillaries and in __________. | altering arterial blood pressure |
Microscopic vessels that connect arterioles to venules. Found near every cell in the body but more extensive in highly active tissue. Function is exchange of nutrients & wastes between blood and tissue fluid | Microcirculation |
Capillary walls are composed of only a ______ of cells and a _______. | single layer; basement membrane. |
_____form branches into capillary bed. Can bypass capillary bed, precapillary sphincters close & blood flows out of bed in thoroughfare channel. | Metarterioles |
_______ is intermittent contraction & relaxation of sphincters that allow filling of capillary bed 5- 10 times/minute | vasomotion |
Types of capillaries | Continuous capillaries, Fenestrated capillaries, Sinusoids |
Why are muscular arteries called distributing arteries? | because they direct blood flow to specific areas |
Intercellular clefts are gaps between
adjacent cells. Found in skeletal & smooth muscle,
connective tissue and lungs | Continuous capillaries |
Plasma membranes have many holes. Found in kidneys, small intestine, choroid plexuses, ciliary process &
endocrine glands | Fenestrated capillaries |
Very large fenestrations. Incomplete basement membrane ␣ found in liver, bone marrow, spleen, anterior pituitary, & parathyroid gland | Sinusoids |
Small veins collecting blood from capillaries. Tunica media contains only a few smooth muscle cells & scattered fibroblasts | Venules |
Consist of the same three tunics as arteries but have a thinner tunica interna and media and a thicker tunica externa.
Less elastic tissue and smooth muscle (thinner-walled than arteries). Have valves to prevent the backflow of blood. Major volume reserv | Veins |
______ are veins with very thin walls with no smooth muscle to alter their diameters. Examples are the brain’s superior sagittal sinus and the coronary sinus of the heart. | Vascular (venous) sinuses |
Twisted, dilated superficial veins. Caused by leaky venous valves. Allow backflow and pooling of blood | Varicose Veins |
The most common sites for varicose veins are in the…. | esophagus, superficial veins of the lower limbs, and veins in the anal canal (hemorrhoids). Deeper veins are not usually susceptible because of support of surrounding muscles |
Union of 2 or more arteries supplying the same body region. Blockage of only one pathway has less of effect because flow
comes via the other artery. Circle of willis underneath brain and coronary circulation of heart. | Anastomoses |
Alternate route of blood flow through an anastomosis is known as | collateral circulation |
Generally, How much of blood volume at rest is in systemic veins and venules? | 60% |
increased muscular activity produces | venoconstriction |
causes venoconstriction to help maintain blood pressure | Hemorrhage |
Movement of materials in & out of a capillary by three methods | Diffusion, Transcytosis, Bulk flow |
passage of material across endothelium in tiny vesicles by
endocytosis and exocytosis | Transcytosis |
is the volume of blood that flows through any tissue in a given period of time | Blood flow |
Total blood flow is cardiac output. | Cardiac output (CO) = heart rate (HR) X stroke volume (SV) |
How the total blood flow becomes distributed into circulatory routes depends on two more factors. | 1.Pressure difference that drives the blood flow
2.The resistance to blood flow in specific blood vessels. |
pressure gradients drive the blood flow. Velocity of blood flow, volume of blood flow, blood pressure
Resistance to flow and venous return | Factors affecting circulation |
Pressure exerted by blood on walls of a vessel. If heart rate increases cardiac output, BP rises. | Blood pressure |
Pressure falls steadily in ____ with distance from left ventricle. | systemic circulation |
Water retention increases _____ | Blood pressure |
Blood pressure drops if…….. | decrease in blood volume is over
10%, |
Caused by friction between blood and the walls of vessels | Resistance |
The factors that influence resistance are? | size of blood vessel lumen, blood viscosity and total vessel length |
smaller vessels offer more resistance to blood flow
Cause moment to moment fluctuations in pressure | Size of lumen |
Ratio of red blood cells to plasma volume. Increases in viscosity increase resistance. Such as dehydration or polycythemia | Blood viscosity (thickness) |
The longer the vessel, the greater the resistance to flow
200 miles of blood vessels for every pound of fat
obesity causes high blood pressure | total blood vessel length |
Volume of blood flowing back to the heart from the systemic veins. | Venous Return |
An electrical event in a cell that leads to the mechanical event (contraction) | action potential or impluse |
Physiology of contraction | Depolarization > Plateau > Repolarization |
Depolarization | excitation spreads between adjacent cells through gap
junctions in the intercalated disks |
Plateau | slow Ca+2 channels open, let Ca +2 enter from outside
cell and from storage in sarcoplasmic reticulum, while
K+ channels close – Ca +2 binds to troponin to allow for actin-myosin cross-
bridge formation & tension development |
Repolarization | Ca+2 channels close and K+ channels open & -90mv is restored as potassium leaves the cell |
ATP production in cardiac muscle is caused by | Aerobic cellular respiration / creatine phosphate |
What is an EKG | action potentials of all active cells detected and recorded |
EKG broken into 3 visible waves : | P wave, QRS complex, T wave |
P wave | Atrial depolarization - spread of impluse from SA node over atria |
QRS complex | ventricular depolarization - spread of impluse through ventricles |
T wave | ventricular repolarization |
Cardiac cycle consists of... | Systole and Diastole of both atria then by ventricles |
Auscultation | the act of listening to sounds within the body |
Cardiac output | The volume of blood ejected from the left ventricle into the aorta each minute. SV x HR = CO |
Factors that effect Stroke Volume : (3) | Preload, Contractility, Afterload |
Preload (Frank-Starling Law) | The more the muscle is stretched there is a greater force of contraction |
Contractility | Autonomic nerves, homrones, Ca2+ K+ levels |
Afterload | amount of pressure caused by the blood in the vessel (high pressure = high afterload) |
Which nervous system increases heart rate and force of contraction | Sympathetic impulses |
Which nervous systen decreases heart rate | Parasympathetic impulses |
Baroreceptors | detect change in blood pressure and send info to the cardiovascular center |
Myocardial infarction | death of area of muscle from lack of O2 (heart attack) |
Angina pectoris | heart pain from ischemia of cardiac muscle |
Coronary Artery Disease | condition in which the heart muscle receives too much blood |
Atherosclerosis | a process in which smooth muscle cells proliferate and fatty substances, especially cholesterol and triglycerides (neutral fats), accumulate in the walls of the medium- sized and large arteries in response to certain stimuli, such as endothelial damage |
Congestive heart failure | a chronic or acute state that results when the heart is not capable of supplying the oxygen demands of the body |
The two mechanisms that "pump" blood from the lower body back to the heart? | Skeletal muscle pump and respiratory pump |
What advantage does a slow rate in the capillaries offer? | Exchanges occur. ex: gas exchange |
Syncope "fainting" | Refers to a sudden, temporary loss of consciousness followed by spontaneous recovery due to cerebral ischemia. |
Role of cardiovascular center | Medulla oblongata helps regulate heart rate and stroke volume |
Innervation of the Heart | Speed up the heart with sympathetic stimulation.
Slow it down with parasympathetic stimulation (X).
Sensory information from baroreceptors (IX). |
Systemic Circulation | left side heart to body & back to heart |
Hepatic portal circulation | capillaries of GI tract to capillaries in liver |
Pulmonary circulation | right-side heart to lungs & back to heart |
Fetal circulation | From fetal heart through umbilical cord to placenta & back |
4 major divisions of aorta | ascending aorta
arch of aorta
thoracic aorta
abdominal aorta |
Largest artery of the body | Aorta |
Ascending aorta | 2 coronary arteries supply myocardium |
arch of aorta | branches to the arms & head
brachiocephalic trunk branches into right common carotid and right subclavian |
Thoracic aorta | supplies branches to pericardium, esophagus, bronchi, diaphragm, intercostal & chest muscles, mammary gland, skin, vertebrae and spinal cord |
Veins of the Systemic Circulation | Drain blood from entire body & return it to right side of heart
Deep veins parallel the arteries in the region |
Major systemic veins | superior vena cava drains the head and upper extremities
inferior vena cava drains the abdomen, pelvis & lower limbs
coronary sinus is large vein draining the heart muscle back into the heart |
What are the lymphatic system functions? | Drain interstitial fluid, Transport dietary fats, carryout specific immune responses |
Lymphatic vessels begin as blind-ended __________ in tissue spaces between cells. | lymph capillaries |
Interstitial fluid drains into lymphatic capillaries, thus forming.. | lymph |
Lymph capillaries merge to form larger vessels, called _______, which convey lymph into and out of structures called _______. | lymphatic vessels; lymph nodes |
ability to fight a specific pathogen | specific resistance |
innate defenses | Nonspecific resistance |
consists of a fluid called lymph flowing within lymphatic vessels, several structures and organs that contain lymphatic tissue | Lymphatic system |
located within lymphatic vessels and lymphatic tissue. | lymph |
found between cells | interstitial fluid |
begin as blind-ended tubes found in spaces between cells | lymphatic capillaries |
These capillaries come together to form | Lymphatic vessels |
Lymph flows through lymph nodes towards the…. | heart |
attach endothelial cells to surround tissue. | Anchoring filaments |
A lymphatic capillary in the villi of the small intestine are called…..
function to transport digested fats from the small intestine into blood. | lacteals |
Found throughout the body except in avascular tissue. Structure allows tissue fluid in but not out | lymphatic capillaries |
Lymph passes from lymphatic ___ into lymphatic ____ and then through lymph ______. | capillaries; vessels; nodes |
Lymphatic vessels exit lymph nodes in a particular region of the body, they unite to form | Lymph trunks |
Which trunk drain lymph from the lower limbs, the wall
and viscera of the pelvis, the kidneys, the adrenal glands,
and the abdominal wall. | Lumbar trunks |
Which trunk drains lymph from the stomach, intestines,
pancreas, spleen, and part of the liver | intestinal trunk |
Which trunk drain lymph from the thoracic wall, lung, and heart | Bronchomediastinal trunks |
Which trunk drain the upper limbs | Subclavian trunks |
Which trunk drain the head and neck | jugular trunks |
Lymph passes from lymph trunks into two main channels: What are the channels? | The thoracic duct (left lymphatic duct) and The right lymphatic duct |
The thoracic duct (left lymphatic duct) begins as a
dilation called the …. And s the main collecting duct of the lymphatic system. | cisterna chyli |
Which duct receives lymph from the left side of the head, neck, and chest, the left upper extremity, and the entire body below the ribs.
Drains lymph into venous blood via the left subclavian vein. | left lymphatic duct |
which duct receives lumph from the upper right side of the body | right lymphatic duct |
Lymph flows as a result of the action of | skeletal muscle contractions and respiratory movements. |
Bean-shaped organs, up to 1 inch long, located along lymphatic vessels | lymph nodes |
Parenchyma is divided into 2 regions: | cortex and medulla |
the site of proliferation of plasma cells (a type of B cell) and T cells. | lymph nodes |
Lymph enters nodes through _____ lymphatic vessels, is filtered to remove damaged cells and microorganisms, and exits through ____ lymphatic vessels. | afferent; efferent |
2 lobed organ located in mediastinum, superior & anterior to the great vessels of the heart. The organ has a capsule and trabeculae that divide the organ into lobules | thymus gland |
tightly packed lymphocytes (T cells) & macrophages | Cortex (thymus Gland) |
reticular epithelial cells produces thymic hormones | Medulla (thymus gland) |
Lymphatic organs and tissues are widely distributed throughout the body and classified into two groups | Primary lymphatic organs and Secondary lymphatic organs & tissues |
Which lymphatic organ provide environment for lymphoid stem cells to divide & mature into B and T lymphocytes | Primary |
The site where most immune responses occur | Secondary lymphatic organs and tissues |
What is the flow of Lymph | Lymph starts as plasma in capillaries, the fluid goes into interstitial spaces and then to lymph capillaries to lymphatic vessels to lymph trunks to the thoracic duct or right lymphatic duct to the subclavian veins |
what promotes the flow of lymphatic fluid | respiratory and muscular pumps |
Lymphatic vessels empty into ….. | subclavian veins |
What region has lymphatic nodules with germinal centers containing dendritic cells and B cells which proliferate into antibody-secreting plasma cells | cortex (lymph nodes) |
What region contains B cells & plasma cells in medullary cords | medulla (lymph nodes) |
The site where pre-T cells that migrate from red marrow mature | thymus |
| Size of Lymph nodes |
5 inch organ between stomach & diaphragm | Spleen |
What does Stroma consists of? | capsule, trabeculae, fibers & fibroblasts |
What does the Parenchyma in spleen consists of? | white pulp and red pulp |
Lymphatic tissue around branches of splenic artery | White pulp is made up of….. |
venous sinuses filled with blood & splenic tissue consisting of RBCs, macrophages, lymphocytes, plasma cells, and granulocytes. | Red pulp is made up of….. |
the production of blood cells during the second trimester of pregnancy is involved in the ... | Red pulp |
The spleen stores _____ in the red pulp. | blood platelets |
Lymphatic Nodules | Concentrations of lymphatic tissue not surrounded by a capsule scattered throughout connective tissue of mucous membranes (MALT) |
Nonspecific resistance | a wide variety of body responses against a wide range of pathogens and their toxins. |
mechanical barriers, nonspecific phagocytosis, chemical defenses | nonspecific defenses |
Mechanical protection | the intact epidermis layer of the skin mucous membranes, the lacrimal apparatus, saliva, mucus, cilia, the epiglottis, and the flow of urine |
Pathogen | disease producing organisms (disruption in homeostasis) |
The second line of defense involves | • internal antimicrobial proteins, • phagocytic and natural killer cells, • inflammation, and • fever. |
Body cells infected with viruses produce proteins called | interferons (IFNs) |
Lymph nodes flow in... | one direction |