Flashcards in Blood vessels exam Deck (158):
efferent and divergent
afferent and convergent
inner most layer of vessels made of endothelium and elastic lamina
middle layer of vessels made of smooth muscle
outer layer of vessels made of connective tissue
Do capillaries have all three layers
no they only have tunica intima
difference between arteries and veins
arteries have thicker walls, more resilient, high pressure, more smooth muscle, and smaller lumen while veins have larger diameter with a larger lumen, have valses, and depend on skeletal muscle to move blood, low pressure
conducting, largest arteries and closest to the heart, highest pressure, expand and recoil in response to pressure.
distributing, medium size, thick muscle layer, distribute blood to specific organs.
recoil of arteries at beginning of ventricular diastole
Swelling in the arterial wall due to localized weakness. Can burst causing hemorrhage.
plaques form as monocytes engulf cholesterol and become foam cells, they stick to endothelial cells and damage it, tissue overgrows, and platelets stick to the damaged wall.
cluster where capillaries are generally found
blood supply to a tissue through a capillary bed
controls the amount of blood flowing into the capillaries. Each capillary-metarteriole junction contains one
small ateriole that feeds each capillary bed
where metarterioles drain into.
tight junctions that permit the diffusion of water, gases, small and lipid soluble molecules (skin and muscle tissue),
pores that permit the diffusion of larger molecules (kidneys, endocrine glands, small intestine)
discontinuous endothelium with large pores that permit very large molecules and blood cells (liver, bone marrow, spleen)
what do the valves of veins do?
extensions of the tunica intima that overlap and prevent backflow
where is most of the blood in the body at?
in the veins called venous reserve
what does the muscles and respiration do for blood movement?
both help propel blood along veins by squeezing the veins when muscles and lungs are contracted/larger in size
blood flows through two consecutive capillary networks before returning to the heart
allows an artery to empty directly into a vein without passing through a capillary bed (provide an alternative pathway for blood),
pathway between two arteries. Exist in many organs like the heart and brain
pathway between two veins
Hepatic portal circulation
the hepatic portal vein brings blood to liver and hepatic veins drain blood from liver.
Blood supply to the brain
the brain is the #1 priority and receives blood from the internal carotid and vertebral arteries.
lungs are collapsed and that blood bypasses the lungs via the foramen ovale and ductus arteriosus
role of the umbilical artery
to return blood to the placenta from the fetus
role of the umbilical vein
to bring blood to the fetus from the placenta
the development of new blood vessels
factors that cause angiogenesis
embryonic development, growth, wound healing, endurance training, obesity, tumors
physiology of blood flow in the cardiovascular system. Heart generates a pressure gradient to overcome the peripheral resistance of blood vessels and generate flow
the amount of blood flowing through an organ, tissue, or vessel in a given time
the flow per given volume or mass of tissue in a given time.
outward force exerted by blood on the walls of blood vessels
how is blood pressure calculated
BP (mm Hg) = CO x PR
main factors that influence blood pressure
CO, PR and Volume
peak blood pressure measured during ventricular systole
minimum blood pressure at the end of ventricular diastole.
pressure is lower in pulmonary or systemic circulation?
rhythmic pressure oscillation that accompanies each heartbeat
high blood pressure (140/90)
low blood pressure (90/50)
how do you calculate pulse pressure
Pulse pressure = systolic – diastolic
How do you measure mean arterial pressure?
MAP (Mean arterial pressure) = diastolic + pulse P/3
what does pressure do as you move from arteries to veins?
body regulates blood pressure to ensure constant blood flow to organs and tissues
Local regulations in specific tissue. Tissues regulates itself.
dilation/constriction of muscles. Can prevent fluctuations in blood flow by making changes in vessel diameter which causes local changes in resistance and flow
maintained by chemicals that are locally released.
In active tissue: low oxygen, high CO2 and low pH and NO, histamine, prostacyclin. Dilating vessels brings more white blood cells
endothelins and thromboxane
Regulates through sympathetic and parasympathetic systems. (faster). Can control constriction of vessels and cardiac output.
Effects of sympathetic NS
speeds up heart, increase cardiac output, causes vasocontraction, increase PR, increase BP
Effects of parasympathetic NS
slows down heart, decrease cardiac output, no effect on vessels but indirectly vasodilation, BP will go down
detect oxygen levels
regulation of homeostasis through the release of hormones (slower). Can affect the amount of blood.
cause CO to increase and bring blood pressure up, cause vasoconstrict
saves water, blood volume goes up, and BP goes up
saves sodium, which saves water, and blood volume goes up. Blood pressure goes up
two-way movement of fluid across capillary walls
the movement of molecules and ions down their concentration gradient. Will diffuse from blood to tissue where concentration is less.
how does the size of molecules affects diffusion across continuous capillaries
proteins cannot diffuse through. rate of diffusion depends of size of gradient and molecule. Continuous capillaries only allow small molecules.
movement of fluid out of capillaries by the hydrostatic pressure
how does filtration work
pressure drives water and solutes out of vessel/capillaries. CHP drives filtration. Pushes water out.
movement of water from tissue back into the capillary. COP drives reabsorption. Colloid Osmotic pressure (COP) pulls water into capillary.
net filtration pressure calculation
NFP = CHP–COP
Overall is there more filtration or reabsorption
NFP positive numbers vs negative numbers
positive= filtration, negative=reabsorption
effects of edema
causes increased CHP and decreased COP, so more filtration
effects of dehydration
decrease CHP increase COP, so less filtration
effects of hemorrhage
results in decreased CHP so less filtration
inadequate pumping of the heart
severe immune reaction to antigen, histamine release, generalized vasodilation, and increased capillary permeability
bacterial toxins trigger vasodilation and increased capillary permeability
functions of the lymphatic system
immunity, regulation of interstitial fluid, absorption of dietary fats
where does WBC production take place?
WBC production in bone marrow and thymus
leukopenia vs leukocytosis
leukopenia = reduced number of WBC caused by HIV or chemotherapy. leukocytosis = increased number of WBC caused by infection or leukemia
general characteristics of WBCs
Generally, don’t perform their functions within the blood
can migrate out of the blood vessels and move via amoeboid movement
are attracted to specific chemical stimuli
many are capable of phagocytosis
neutrophils, eosinophils, basophils
monocytes and lymphocytes
most abundant, multilobed nucleus, attracted by dying tissue or bacterial secretion
attack and kill pathogens like bacteria by releasing granule content or by phagocytosis, contribute to local inflammation, attract other immune cells
dead neutrophils and other debris
what does high numbers of neutrophils mean
indicator of inflammation
large red granules contain cytotoxic, bilobed nucleus
effective against large parasites through exocytosis of toxic compounds on the parasite
very rare, large dark granules, contain histamine and heparin
activated by IgE antibodies, role in allergic reactions
largest leukocytes, no granules, u shaped nucleus, when they exit the blood they are called macrophages
aggressive and long-lived phagocytes, engulf and destroy pathogens, attract other immune cells activate other components of immune system by displaying phagocytosed antigens
difference between free and fixed macrophages
free = circulating, fixed = resident tissue macrophages
small cells with large spherical nucleus and a light blue rim of cytoplasm
production of b cells in bone marrow and t-cells in thymus
lymph compared to plasma
has low protein content compared to plasma
difference between systemic circulation capillaries and lymphatic capillaries
lymphatic capillaries have larger diameter, are blind ended for a one-way system, and are leakier
what do larger lymphatic vessels have?
blockage of lymphatic drainage from a limb
Natural killer cells
large lymphocytes that do immunological surveillance
natural killer, T cells, B cells, dendritic cells, reticular cells, and macrophages
mobile cells found in the epidermis and mucous membranes that present pathogens to immune system cells
type of fibroblasts that produce reticular fibers and provide structural support for lymphatic organs
reticular tissues dominated by lymphocytes
loosely organized clusters of lymphoid tissue, which includes tonsils, payer's patches, and appendix
located in last portion of small intestine
lymph node structure
small, bean-shaped clusters of lymphatic tissue surrounded by capsule of connective tissue located along lymphatic vessels
lymph node function
to filter lymph and detect antigens and initiate an immune response
three types of tonsils
pharyngeal tonsil, palatine tonsils, and lingual tonsil
red pulp in the spleen
contains macrophages which destroy old RBCs
white pulp in spleen
filters pathogens from blood and contains leukocytes and dendritic cells
function of spleen
thymus does what with age and is important for?
its size changes with age and importance for T cell production and maturation
the proteins, calls, and tissues responsible for defending the body against both environmental hazards and internal threats
molecules that cause disease
three lines of defense
o First line: cutaneous and mucous membranes that act as a barrier to block entry of pathogens
o Second line: responses of cells and proteins that make up innate immunity
o Third line: includes responses of cells and proteins of adaptive immunity
innate immune response
first line of defense. We are born with it. quick and non-specific, respond to any pathogens, barriers always there even if no stimulus
adaptive immune response
longer and highly specific, will recognize one specific pathogen, and remembers what it has encountered from before. carried out by humoral (b-cell mediated) and cell mediated (t-cells)
surface barriers of innate immunity
hair, skin, and mucous membranes, sebum, sweat, saliva, stomach acid
fever, compliment system, cytokines
engulf pathogens; macrophages, neutrophils and eosinophils
local tissue response to injury
stages to inflammation
injury, inflammatory mediators released, inflammatory mediators trigger: vasodilation, increased capillary permeability, pain, recruitment of other immune cells
signs of inflammation
redness, swelling, heat, pain
properties of innate immunity
surface barrier, immunological surveillance, physiological responses, phagocytes, inflammation
properties of adaptive immunity
specificity, versatility, memory, and self-tolerance
each T or B cell responds only to one specific antigen and ignores the others
the body can recognize many types of antigens
memory of adaptive immunity
memory cells stay in circulation and when re-exposed to the same pathogen the body reacts quicker
“docking sites” for specific components of antigens that are then displayed
MHC class 1
found on all nucleated cells. Recognized by cytotoxic t cells. Present antigens found inside the cell
MHC class 2
found on specific immune cells. Recognized by helper t cells. Present antigens taken in by phagocytosis
cell mediated response
responds primarily to cells infected with intracellular pathogens (virus, cancer, transplanted organs…)
steps to cytotoxic T cell response
• activation: T cell recognizes an antigen presented on MHC class 1.
• Cell division to make copies of activated t cell
• find and destroy abnormal cells presenting the antigen
• some t cells stay in circulation and become memory cells
steps to helper T cell response
• activation: recognize an antigen presented by MCH class 2
• cell division and make copies
• helper t cells release cytokines (chemicals) to activate immune response
• Some become memory cells
steps to antibody-mediated B cell response
• Activation: b cell receptor recognizes an antigen. B cell presents the antigen to helper t cell. Helper t cell releases chemicals to activate b cell.
• Cell division to make copies
• B cell becomes a plasma cell and releases antibodies
• Some b cells become memory cells
location and function of v region of antibodies
where the antibody binds to antigen
classes of antibodies
IgG: most abundant and can cross the placenta
IgE: involved in allergic reactions
IgD: on the surface. The b cell receptors
IgM: first to be produced by plasma cell
IgA: work together in innate immunity
how do antibodies work?
neutralization, agglutination, complement fixation, and opsonization
prevent pathogens and toxins from interacting with out cells
antibodies stick to each other
coat pathogen and enhance phagocytosis
primary immune response
first time you are infected with certain pathogen
secondary immune response
re-exposure to pathogen
active natural vs active artificial
N = through exposure via infection, A = through vaccination
own immune system makes antibodies
receive antibodies from someone else
passive natural vs passive artificial
N = mother’s milk, A = : inject antibodies to toxins or venoms (being bit by a snake, rabies…)
principles of graft rejection
cytotoxic t cells and NK cells attack foreign cells and cause necrosis
immune system incompetent (not working). ex: HIV/AIDS
immune system treats self-antigens as foreign and attack own tissue
cause the immune system to overreact which can damage tissues