✧*̥˚ a&p : blood vessels and lymphatic system *̥˚✧

arteries

strong thick walled carrying blood away from the heart and under high pressure

arteries subdivide into…

arterioles

arterioles

carry blood to capillaries (gas and nutrient exchange)

arterial wall layers?

tunica intima, tunica media, and tunica externa

tunica interna/intima

is simple squamous epithelium

tunica media

middle smooth muscle layer w/ collagen and in some cases elastic fibers

tunica externa

is the thin outer layer of the vessels

the tunica externa is made of?

loose areolar connective tissue

elastic arteries is also called

conducting arteries

the largest artery?

elastic arteries

what is the elastic arteries?

\-large amount of elastic fibers in thick tunica media; larger diameter size.

\-examples include, aorta, pulmonary trunk, common iliac arteries

muscular arteries size?

medium

muscular arteries aka

distributing arteries

what is muscular arteries?

\-has thick media w smaller diameter

\-capable of greater vasoconstriction and vasodilation to adjust blood flow

\-distribute blood to various organs

anastamoses

\-union of the branches of two or more arteries supplying the same body region

\-provide alternate routes, for blood to reach organs due to blockage

\-collateral circulation

\-occur between arterioles and venules

vasoconstriction

increase resistance and increase blood pressure

vasodialtion

decrease resistance and decreases blood flow

capillaries

have a walls of simple squamous epithelium

capillaires allow for exchange of

gas and nutrients with tissue fluid

microcirculation

flow of blood into the bed via arterioles and blood exits via venules, blood flow through capillaries

continuous capillaries

formed by endothelial cells held together by tight junctions with interruptions called intercellular clefts which allow for the passage small solutes

fenestrated capillaries

cells of the endothelium contain many small pores, that allow for rapid passage of small solutes

sinusoids capillaries

wide winding capillaries with unusually large fenestration and wide intercellular clefts

venules

drain blood from most capillaries then join to form veins that return blood to heart

viens are lower in and higher in?

o2 and wastes

veins valves

prevent backward flow of blood when closed and make sure blood is moving towards the hearts

veins/venules carry about ____ of the bodys blood

64%

mechanisms of venous return

* pressure gradient
* gravity
* cardiac suction
* skeletal muscle pump
* respiratory pump

circulatory shock

happens when CO is insufficient to meet body’s metabolic needs

arterial end

blood pressure > osmotic pressure

venous end

osmotic pressure > blood pressure

edema

accumulation of fluids in tissues that occur when fluid filtered out of blood and into tissues faster than it is reabsorbed back into blood.

right ventricular failure

lead to systemic edema

left ventricular failure

leads to pulmonary edema

reduced capillary reabsorption

reduced plasma albumin concentration - hyproteinemia can cause liver failure or edema

obstructed lymphatic drainage

the lymphatic system responsible for returning about 10% of tissue fluid back to blood, if blockage occurs with this reabsorb system, edema can result

flow

amount of blood flowing through an organ/tissue/blood vessels at any given time

perfusion

the flow per given volume or mass of tissue, usually in mL per 100 grams of tissue per minutes

blood pressure

force that blood exerts against vessel wall

where is BP measured

brachial artery

what device measures bp

sphygmomanometer

systolic pressure

peak arterial pressure during ventricular systole top #

diastolic pressure

minimum arterial pressure during ventricular diastole (relaxation) bottom #

hypotension

chronic low resting bp less then 90/60

hypertension

chronic resting bp higher then 140/90

pulse pressure

differences between diastolic and systolic pressures

factors affecting resistance

* blood viscosity
* vessel length
* vessel radius/diameter

angiotensin II

strong vasoconstrictor that raises BP when too low

aldosterone

released from adrenal cortex, raises BP, signaling kidneys to retain sodium, urinate less.

ANP (atrial natriuretic peptide)

released from atrial cells, antagonist to aldosterone so lowers BP

ADH (antidiuretic hormone)

raises bp, by promoting water retension by kidney, released from posterior pituitary.

epinephrine and norepinephrine

released from adrenal medulla and sympathetic neurons casues vasoconstriction, raises BP.

simplest pathway

heart → arteries → capillaries → veins → heart

portal system

heart → arteries → 1st capillary bed → portal vein → 2nd capillary bed → veins → heart

arteriovenous anastomosis

heart → arteries → vein → heart

venous anastomoses

vein draining a capillary bed join w/ another vein to provide alt routes of blood draining from an organ. this is why vein blockages are not as life threatening as artery blocks

arterial anatomoses

when 2 arteries merge to provide collateral routes of blood supply to a tissue common in coronary circulation and around joints

the lymphatic system

network of vessels structures and organs that assists in circulating body fluids (lymph) and production of immune cells.

lymphatic system functions

1. fluid recovery
2. immunity
3. liquid absorption

lymph

clear colorless tissue that has left the tissue spaces and entered a lymphatic capillary

lymphatic pathways

lymphatic capillary → lymphatic vessels → lymph nodes →lymphatic vessels →lymphatic trunk → collecting ducts →subclavian veins

lymphatic trunks

* jugular
* subclavian
* bronchomediastinal
* intercostal
* intestinal
* lumbar

lymphatic collecting duct

* thoracic
* right lymphatic

trunks of draining into right lymphatic ducts

* right jugular
* right subclavian
* right bronchomediastinal

trunks draining into thoracic duct

* right/left lumbar
* intestinal trunk
* left bronchomediastinal
* left subclavian
* left jugular

flow of lymph is?

slow and low pressured

mechanism of the flow of lymph

* lymphatic vessels contract
* skeletal muscle contraction
* respiratory movement
* presence of valves

natural killer cells

large lymphocytes that target bacteria/infected host cells

t-lymphocytes

targets similar to NK cells

b-lymphocytes

antibody secreting cells that target a variety of pathogens

macrophages

phagocytic cells that target tissue debris, dead cells, bacteria, and other foreign materials

dendritic cells

mobile antigens presenting cells involved in activation of immune system

reticular cells

stationary APCs and found in lymphatic organs

MALT

diffuses lymphatic tissue located in connective tissue underlying mucous membrane

peyer’s patches

specialized clusters of MALT, underlying the epithial layer of the ileum in the small intestine

lymph flows into the lymph node via ?

afferent lymphatic vessels

lymph flows OUT of a lymph node via ?

efferent lymphatic vessels

lymph nodes filter out?

harmful particles out of lymph fluids

hilum

identation on concave side of node where efferents exit and arteries/veins enter and leave node

spleen function

filters blood

red pulp?

concentrated w rbcs; will remove old worn out rbcs and phagocytized by macrophages

white pulp?

regions concentrated with lymphocytes/macrophages monitor blood for foreign invaders

3 characteristics of innate immunity

local, non specific, and lacks memory

external barriers are???

skin, mucous membrane, and hair

phagocytosis

cellular eating by certain leukocytes

* destruction of foreign particles by engulfing the foreign invader

macrophages

cells develop from larger wbcs such as monocyte; termed macrophages once they leave blood and take up phagocytic role

neutrophils

target bacteria in connective tissue consumed at the end of of their response to pathogen

interferon

protein released by some viral infected cells serves to protect neighboring cells

3 major processes of inflammation

1. mobilization of defenses
2. containment and destruction of pathogens
3. tissue cleanup and repair

adaptive immunity

* systemic
* specific
* remember

cellular immunity

involves lymphocytes directly attacking and destroying foreign cells or diseased cells

humoral immunity aka (antibody mediated immunity)

involves production of antibodies which dont destroy pathogens, may be classified as passive or active.

antigens stimulate

the production of antibodies

APCS (antigen presenting cells)

* b cells
* macrophages
* reticular cells
* dendritic cells

mch stands for????

major histocompatibility complex

opsonization

coating antigens with antibodies to make antigens easier target of phagcytosis

precipitiation

enhances phagocytosis by grouping together individual cells or ag molecules making them immobile and less able to spread; easier targets for phagocytes

neturalization

blocks the ability of ag to adhere to host cells by coating the ag with abs, diminishes pathogenicity

complement fixation

abs interact.attract complement proteins causing cytolysis of microbial cell

cytotoxic t cells (Tc)

t cells that carry out direct attacks on antigens