J Cards (Circulatory System) and K Cards (Heart Structure & Function) | Unit C

DOES NOT INCLUDE VASCULAR PATHWAYS

artery

strong, thick walled. composed of inner endothelium, elastic tissue and smooth muscle, and outer connective tissue.

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carries blood away from heart under high blood pressure

artiole

small vessels that branch off arteries. composed of thick layer of smooth muscle and less elastic tissue.

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found only in organs, alters lumen diameter to control blood flow

constriction ↑BP

dilation **↓**BP

capillary-exchange area

walls one squamous empithelium cell thick (BEST EXCHANGE). less BP + velocity.

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allows exchange of fluids, nutrients, and gasses between blood and cells

arteriovenous shunt

direct connection from arteriole to venule

venules

small veins. thin, distensible vessel. large lumen diameter.

carries deox blood from capillaries into veins. one-way waves from skeletal muscle contraction and respiratory movements prevent backflow

one-way valves

from skeletal muscle contractions. increases BV

veins

thin, distensible vessel w/ large lumen. lacks skeletal muscles, NOT SMOOTH. little lumen to maintain pressure, BP lower.

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carries deox blood from venules to heart. one-way waves from skeletal muscle contraction and respiratory movements prevent backflow (BV↑)

hemorrhage

bleeding, constricts veins and venules, diverting blood to vital organs

right side of heart

pumps blood to lungs

left side of heart

pumps blood to all other body locations

pericardum

tough, fibrous, loose sac, surrounds heart. contains pericardial fluid

pericardial fluid

lubricating fluid found in pericardium. reduces friction

myocardium

contractile layer of cardiac muscle. only found in heart, fibers form junctions and an interconnected network that allows rapid transmission of electrical impulses through heart

atria (general)

thin walled, pulses together.

ventricles (general)

inferior to each atrium. thick muscular walls contract together.

septum

internal wall, divides heart into right and left side

atrioventricular valves (AV valves and cuspid valves) (general)

found between atria and ventricles. prevents backflow of blood. cusps held together by chordae tendinae

semilunar valves (general)

where major artery exits from ventricle. prevents backflow of blood

tricuspid valve

AV Valve, between RA and RV

bicuspid/mitral valve

AV valve, between left atrium and left ventricle

pulmonary semilunar valve

between right ventricle and pulmonary trunk

aortic semilunar valve

between left ventricle and ascending aorta

chordae tendinae

heartstrings, prevents valves from inverting

papillary muscles

elevated masses of muscle tissues in ventricles

superior/anterior vena cava

thick vein, drains deox blood from head, neck, arms, into RA

inferior/posterior vena cava

thick vein, drains deox blood from lower body regions

pulmonary trunk

RA → right and left pulmonary arteries

pulmonary arteries

left and right version. flows into lungs for oxygenation

pulmonary veins

2 from each lung. returns oxygenated blood to left atrium

pulmonary circulatory system

carries deox blood to lungs, ox blood back to heart

aorta

blood from LV → all other regions of the body except for lungs

coronary arteries

branches off aorta shortly after the exit from left ventricle. carries ox blood back to heart tissue

systemic circulatory system

includes vessels that carry blood to and from body cells

cardiac cycle

each heartbeat, end-to-end period of one contraction to another

systole

contraction

diastole

relaxation

atrial systole

happens first in cardiac cycle

ventricular systole

happens second in cardiac cycle

diastole

both ventricle and atria relax. happens third in cardiac cycle

“Lub” heartbeat

AV valves close, ventricles contracts

“-dup” heartbeat

semilunar valves close

pulse

expansion and recoil of artery walls due to blood pressure. cannot be found in a vein due to low blood pressure

initiation of heartbeat

comes from heart itself, not dependent on central nervous system

extrinsic control of heartbeat

medulla oblongata sends impulses down sympathetic/parasympathetic nerve to SA and AV node to increase/decrease heart rate

nodel tissues

specialized cardiac muscle tissues that stimulate heart to beat

sinoatrial (SA) node

found in wall of right atrium. pacemaker, sends out excitation impulse, causing atria to systole

atrioventricular (AV) node

found in base of right atrium near septum.

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receives the wave of contraction down atria initiated by SA node → allows atria to fill ventricles → produces its own excitatory impulse, initiating ventricular contraction

body of his

receives impulse transmitted by AV node. divides into right and left branch

purkinje fibers

located within ventricular walls

activated by body of his → rapidly transmits impulse to all parts of the ventricles → ventricles contract as a unit → max pressure exerted → blood forced throughout body

blood pressure

force exerted by blood against inner walls of blood vessels. caused by heart contractions. depends on cardiac output and resistance to blood flow imposed by blood vessels

systolic pressure

higher arterial pressure, produced by contraction of left ventricle (↑BP)

diastolic pressure

BP drops to lower number since left ventricle relaxes

pulse pressure

difference between systolic and diastolic pressure

hypertension

high BP. usually no symptoms, but heightened risk of heart attack, stroke, kidney, and eye damage (glaucoma)

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* being overweight
* family history
* being Indigenous or African descent
* inactive lifestyle
* too much alcohol
* too much NaCl
* insufficient K, Ca, Mg
* using birth control pills, steroids, decongestants, anti-inflammatory drugs
* smoking
* high cholesterol diet

hypotension

low BP. no symptoms, good health as less stress on heart and blood vessels.

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symptoms:

* dizziness
* fainting

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caused by:

* dehydration
* infection
* heart disease
* adrenal insufficiency
* bleeding out
* prolonged bed rest
* poisoning
* toxic shock syndrome
* blood transfusion reactions

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drugs that can cause:

* BP drugs
* diuretics (water pills)
* heart medications
* depression medications
* alcohol

cardiac output

volume of blood per minute left ventricle pumps into aorta. impacts BP and blood velocity

BP and BV are highest

near the heart

BP and BV decline rapidly

as blood enters arterioles → resistance to blood flow caused by friction between blood and arteriole inner walls

total cross-sectional area of capillaries

causes BP and BV to drop. total combined width is much greater, lowered BP and BV

far distance away from heart

BP and BV lower

gentle flow of blood for exchange of substances in capillary blood

BP and BV lower

bottle neck effect

decrease in total cross-sectional area in veins → BV increases

functions of blood

T ransport of O2, nutrients, hormones, CO2, other wastes

T hermoregulation by capillaries and blood surface

I mmunity via leukocytes (WBC)

C lotting by platelets and clotting proteins

A cid-base regulation (H+, HCO3-)

cellular components/formed elements

composes 45% of blood

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* red blood cells
* white blood cells
* platelets

liquid plasma

yellow, composed of water, dissolved or suspended molecules like glucose, electrolytes, amino acids, lactic acid, urea, minerals, hormones, enzymes, antibodies

plasma proteins

albumin, globulins, fibrinogens

albumins

maintains osmotic pressure, mostly made by liver

globulins

play roles in transportation, clotting, and immunity. formed by lymphocytes (WBC)

fibrinogens

play roles in transportation, clotting, and immunity. formed mostly by liver

protein content in blood

determines osmotic pressure, molecules too large to pass through capillary membranes

serum

blood - formed elements - protein

plasma electrolytes

ions like Na+, Cl-, K+, Ca+2, PO4-3, SO4-2, Mg+2, HO3-

red blood cells/erythrocytes

flexible, biconcave disks. lacks nuclei at maturity

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carries hemoglobin

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low O2 levels in arterial blood → kidneys stimulated to produce erythroprotein →stimulates erythroblast stem cells in red bone marrow → new made!

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lives for 120 days → 4 heme groups sent to liver to be reused → each heme group binds to 4 O2 molecules → globin converted into bile (bilirubin and biliverdin) by liver

anemia

produced by low RBC count and/or hemoglobin deficiency. inability of the blood to carry and deliver sufficient oxygen to body cells

white blood cells/leukocytes/lymphocytes

larger cells, translucent, have nuclei

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produced in bone marrow, spleen, and lymphatic tissue (lymph nodes)

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changes shape, slips through capillary walls into tissue, hunts bacteria, viruses, protists, fungi, and own cells

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lives for 4-8 hours in blood, 4-5 days in tissue

leukemia

when one type of WBC produced excessively in bone marrow. causes insufficient room for RBC and platelets → anemia and clotting problems. WBC are abnormal and unable to function

neutrophils

phagocytosis to form pus

eosinophils

phagocytize antigen-antibody complex

basophils

releases histamine → capillaries become more permeable → more things able to go through to tissue to fight

monocytes/macrophage

phagocytosis & stimulates other WBC production

lymphocytes B-cells

produces antibodies, processed in bone marrow

lymphocytes T cells

destroys specific target cells directly. processed in thymus gland

platelets/thrombocytes

moves along blood vessel → attracted to rough texture on interior → plugs holes → initiates blood clotting

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small cellular fragments from megakaryocytes

megakaryocytes

giant cells, pinches off bits of cytoplasm, releases into blood, forms platelets/thrombocytes

electrocardiogram/ECG/EKG

records myocardium’s potential difference (voltage, electrical impulses)

P Wave

depolarization (exchange of NA+ and K+) of atria → atrial systole

QRS complex

depolarization (exchange of NA+ and K+) of ventricles → ventricular systole

T wave

polarization of ventricles → ventricular diastole

why is diastole of atria not recorded

too small, can’t be detected

extracellular fluid/tissue fluid/intestinal fluid

surrounds cells, contains water, glucose, O2 to supply body cells

capillary fluid exchange BP>OP

arterial end of the capillaries. happens because closer to the heart and high total cross-sectional area. **ECF forced out into intracellular space**

capillary fluid exchange OP>BP

venous end of capillaries. happens because plasma proteins and salt make blood hypertonic, causing fluid to enter capillaries from tissue spaces via osmosis. **ECF returns back into capillaries**

edema

tissue swelling. starving individuals digest plasma proteins as last source of energy → decrease in osmotic pressure → less fluid enters back into capillaries → most fluid is outside in cells, → swelling

lymphatic system functions

1) transports lymph via lymph vessels back to blood

2) lacteals absorb fat at intestinal villi → transports back to bloodstream

3) protects the body from bacterial infection

lymph

tissue fluid, transported in lymph vessels back to blood, contributes to blood plasma. contains more protein than ECF

lacteals

found in intestinal villi, absorbs fat, transports back to bloodsteam

lympatic organs

L ymph Nodes

S pleen

T hymus Gland

B one Marrow

T onsils

lymph capillaries

microscopic vessels, takes up lymph not reabsorbed by systemic capillaries.

lymphatic vessels

collection of many lymph capillaries. parallels venules and veins. lymph flows through this via skeletal muscle contraction, intestinal peristalsis, and gravity. has valves that prevent backflow

right lymphatic duct

drains lymph from right arms and right halves of head and thorax. empties on right subclavian vein