Lab EXSC

blood gets its bright red color from transporting high amounts of

oxygen binded to hemoglobin

oxygen transported in the blood via red blood cells aka

erythrocytes

erythrocytes contain oxygen carrying protein

heme

hematocrit

percentage of blood volume occupied by red blood cells; 45%

formed elements

white blood cells, red blood cells, platelets

what are white blood cells called and what is their function

provide defense against pathogens and immunity

neutrophils

most abundant white blood cell; granulocyte with a multilobe nucleus; phagocytizes bacteria and debris

lymphocytes

agranulocyte; spherical nucleus; mounts immune response by direct cell attack or via antibodies: T cells and B cells; natural killer cells

monocytes

agranulocyte; kidney shaped nucleus; turns into macrophage when it exits the blood; phagocytosis of pathogens and debris

eosinophils

granulocyte with bilobed nucleus; red granules; kills parasitic worms and has a complex role in allergy and asthma

basophils

granulocyte with large purple and black granules and a bilobed nucleus; release histamine and other mediators of inflammation, contain heparin, an anticoagulant

55% of blood is

plasma

plasma is 90%

water

10% of plasma is

proteins (albumin for osmotic balance, fibrinogens for clotting, globulins for antiboies and lipid transport), gases (carbon dioxide and pH balance), nutrients (carbs, fats, proteins, micronutrients, electrolytes, enzymes), metabolic waste, hormones

increase in red blood cells

polycythemia

how does oxygen availability impact RBC counts

kidneys baroreceptors sense low oxygen levels, and produce more erythropoetin which stimulates the bone marrow to produce more red blood cells

why does the lumen of the artery have a scalloped squiggly outline while the vein is elongated and collapsed

arteries have thicker walls than veins because their tunica media have more smooth muscle and elastic tissue allowing for constriction and dilation of vessels to regulate BP. Veins are squeezed by skeletal muscles to pump blood through them

which vessel serves a more active role in blood pressure regulation and response

arteries

arteries transport blood from the \______ to the \_____ and \_____

heart; lungs and tissues

vins transport blood from the \_____ and \_____ to the \____

lungs and tissues to the heart

do all arteries carry oxygenated blood

no; pulmonary arteries carry deoxygenated blood because they carry blood that has returned to the heart via the systemic circulation from tissues to the lungs to become oxygenated

Path of a drop of blood through the heart

returns through vena cava to right atrium through right AV valve: tricuspid to right ventricle through pulmonary semilunar valve to pulmonary trunk to pulmonary artery to lung to pulmonary vein to left atrium through left AV valve: mitral bicuspid valve to left ventricle through aortic valve to aorta

valve open and closures

AV valves open as blood passively flows from atria to ventricle, atria contracts and AV valve is still open (semilunar valves are closed), blood fills ventrile, ventricle then contracts, causing the AV valve to close due to tension on chordae tendinae from papillary muscles, when pressure is greater in ventricle than in pulmonary trunk/aorta, semilunar valve opens, and blood rushes into vessel, when pressure decreases in ventricle, blood falls back in vessel into the cups of the semilunar valves, closing the valve

cardiac cycle on EKG

P wave is atrial deploarization due to SA node, QRS complex is ventricular depolarization and atrial repolarization, T wave is ventricular repolariation

SA node phases

Phase 4: resting membrane potential: calcium in intersitial fluid, sodium is leaking across membrane causing membrane potential to rise (slow depolarization) until threshold is reached; Phase 0: depolarization: calcium channels open and calcium rushes into the cell, the myocardium contracts, calcium channels close when membrane potential becomes positive

Phase 3: potassium channels open and potassium and repolarize the cell

ventricular myocyte action potential

Phase 0: depolarization: opening of fast sodium voltage gated channels from SA node firing

Phase 1: brief absolute refractory period, fast sodium voltage gated channels close, potassium channels open

phase 2: plateau (prolonged absolute refractory period): potassium channels close, calcium channels open keeping the ventricular myocytes depolarized, delays repolarization

Phase 3: repolarization, closure of calcium channels, reopening of potassium channels

phase 4: rest

4 major processes of respiratory system

pulmonary ventilation: breathing

external respiration: gas exchange between alveloi and blood

internal respiration: gas exchange between blood and tissue

transport: gas circulation between lungs and tissues

describe the travel of air

Air enters the trachea \= windpipe then between the 4th and 5th thoracic vertebrae, divides into the right and left main or primary bronchi before entering the hilum of each lung (medial concavity). These further divide into secondary (to each lobe) or lobar bronchi, segmental bronchi (tertiary) and so on until they for respiratory bronchioles à alveolar ducts à alveolar sacs or alveoli (simple squamous epithelium).

where is trachea located

between 4th and 5th thoracic vertebrae

respiratory membrane

the wall of the alveloi and the wall of the capillary

respiratory zone includes

alviolar sacs, alveolar ducts, respiratory bronchioles

what type of tissue is blood

atypical connective tissue

functions of blood

transprots nutrients (oxygen) to body cells and brings waste (carbon dioxide) from cells; trasnports hormones, regulates body temp, protects body from pathogens, clots to prevent blood loss

platelets

seal small tears in blood vessels; essential for clotting

how does plasma maintain homeostasis

by releasing heat

what bone marrow are RBCs produced in

vertebrae, sternum, ribs, pectoral girdle, pelvic girdle

hemocytoblasts

stem cells that give rise to different blood cells

mature RBCs

hemocytoblasts eject nucleus

how do mature RBCs enter the bloodstream

via sinusoids

percentage of white blood cells in blood

1%

b cells

produce antibodies

t cells

target viruses, fungi, cancer, transplanted cells

natural killer cells

attack and destroy foreign microbes

percent of blood that are platelets

2%

how do platelets stop blood loss from damaged vessels

blood vessel tears, platelets adhere to the wall of the vessel to close the tear, platelets release chemicals that activate the coagulation system, clotting factors form fibrin threads

cells that sheds to form platelets

megakaryocytes

anemia

decreased oxygen carry capacity; can be decreased RBC count, hemorrhage, etc

location of heart

in medial cavity surrounded by lungs, vertebral column, sternum

apex

bottom of the heart slightly to the left

base

top of the heart

where do the greatest vessels leave the heart

the base

septum that divides the heart longitudinally

interatrial or interventricular septum

pressure of the blood entering the atria

low pressure

2 circuits of blood flow

pulmonary and systemic

right ventricle sends blood to the

pulmonary circuit

left ventricle sends blood to the

systemic circuit

attach valves to papillary muscles

chordae tendineae

diastole

period of ventricular filling (AV valves open)

systole

when ventricles contract/empty (AV valves close)

heart sounds

lub dub

first heart sound

lub: AV valves close and signifies beginning of ventricular systole

second heart sound

dub: semilunar valves close at the beginning of ventricular diastole

what muscle in heart contracts during systole

myocardium

Heart excitations

SA node generates impulse, atrial excitation begins, impulse delayed at AV node, impulse goes to bundle of His, bundle branches to begin ventricular excitation, and travels to purkinje fibers to complete ventricular excitation

ECG

electrocardiogram: grahic recording of electrical events, established electrode pattern results in specific tracing pattern, electrical pattern reveals blood supply problems

enlarged R wave

enlarged ventricles

prolonged P-R interval

first degree heart block: signal from SA node to the AV node is delayed longer than normal

Prolonged Q-T interval (when compared to the R-R interval)

increased risk of ventricular arrhythmias, interval corresponds to the beginning of ventricular depolarization through ventricular repolarization

S-T segment elevated from baseline

myocardial infarction (heart attack)

tunica intima

endothelium, subendothelial layer, internal elastic membrane

tunica media

smooth muscle and elastic fibers; external elastic membrane

layers of blood vessels

tunica intima, tunica media, tunica externa

tunica intima

innermost layer, lines the lumen of the vessel

endothelium

simple squamous cells that create a smooth lining of vessel\=decreased resistance to blood flow

subendothelial layer

surrounds endothelium

internal elastic membrane

only in arteries

tunica media

middle layer; primarily smooth muscle and elastin; actively involved in regulating vessel diameter

tunica externa

areolar and fibrous connective tissue; support and protect the vessel

what vessel is only composed of endothelial cells surrounded by a basement membrane

capillaries

transport blood away from the heart

arteries

transport blood back to the heart

beins

Veins contain \_____________________ to prevent backflow of blood

valves

what is skeletal muscles function in veins

their pumping promotes venous return by milking the blood towards the heart

veins are named for

areas or organs the remove waste and byproduct from

circle of willis

cerebral arterial circle; anterior cerebral artery, middle cerebral artery, posterior cerebral artery, posterior/anterior communicating brances

elastic arteries

largest most elastic arteries; expand and recoil for continuous blood flow; conducting

examples of elastic arteries

aorta, brachiocephalic, common carotid

muscular arteries

distributing, medium sized arteries, account for most arteries found in body, less elastic tissue and more smooth muscle tissue, better ability to constrict, distribute blood to specific areas of the body

contain only a tunica intima

capillaries

arterioles

smallest arteries with thin tunica externa; regulate blood flow to specific areas of the body

venules

smallest veins; drain capillary beds and merge to form veins

veins

ontain more fibrous tissue in tunica externa, thinner tunica media but larger lumen than arteries, low pressure vessels

pulmonary ventilation

flow of air into and out of lungs

external respiration

gas exchange between blood and the air filled chambers of the lungs

gas transport

transport of respiratory gases between lungs and tissue of body using blood

respiratory structures also support

olfaction and phonation

upper respiratory system

nasal and pharyngeal structures

function of nasal structures

passage for air into respiratory system; filter, warm, and moisten the incoming air

pharynx

provides passage for air to lower respiratory system: nasopharynx, oropharynx, laryngopharynx

pharyngotympanic tube

allows the ears to equilize middle ear pressure with that of the atmosphere; ear popping