unit C - circulatory Flashcards
percentage of red blood cells
hermatocrit
erythrocytes
red blood cells
-produced in the bone marrow
-45% of blood
carries oxygen
plasma
-mixing of water and blood proteins
-55%
dissolved minerals, holds blood cells in suspension
leukocytes
white blood cells
-produced in the bone marrow
-less than 1%
to destroy microbes and make antibodies
thrombocytes
platelets
-produced in bone marrow
-less than 1%
cause blood clotting, forming a plug to stop body from bleeding out
blood clotting
process of forming a plug to stop the body from bleeding out
hormone that stimulates blood production
EPO (erythropoietin)
sickle cell anemia
blood shape is similar to a sickle
- not as much surface area
- oxygen cannot find the hemoglobin
three particles of blood (scientific names)
erythrocytes, leukocytes, thrombocytes
main functions of the cirulatory system
- TRANSPORTS gases, nutrients and waste throughout body
- REGULATES the internal temperature and transports homrones
- PROTECTS against diseases and blood loss
bloodletting
belief that it is healthy to have parts of your blood removed from the body
arteries (direction)
carry blood away from the heart
veins (direction)
carry blood toward the heart
capillaries (direction)
joins each artery and vein
-site of gas and nutrient exchange
three main types of blood vessels
- veins
- arterties
- capillaries
blood travels
from the heart to the arteries to capillaries to veins back to the heart
arterioles
smaller arteries
-getting very narrow, going to transistion to capillaries
venuoles
smaller veins
-getting very narrow, going to transistion to capillaries
whats on either sides of capillaries
arterioles and venuoles
artery
- extremely big beefy and strong
- very stretchy
why are arteries so thick/beefy/strong
need to withstand blood pressure, since blood coming from the heart has very high pressure
what is a pulse
a pulse is when the blood surges through the artery, and there is a slight bulge or wave
capillaries
- very small, one cell thick, fragile
- allows for gas exchange, difussion and nutrient exchange
every cell is how far from a capillary?
100 micrometers
vein
- not as elastic
- thinner walls, thinnger inner circumference
valves in veins
since blood is fighting against gravity, these one way valves prevents backflow
why are some of our blood vessels closed
we only have six litres of blood, and if all the blood vessels were open we would need over 100 liters of blood
pre-capillaries sphincter
band of smooth muscle surrounding the capillaries that control the amount of blood flow
where are arteries found
all over the body but deeper into tissues etc
better protection
where are veins found
all over the body but usually closer to the surface
blood pressure in artery
80-129 mm Hg (high pressure)
blood pressure in veins
15-20 mm Hg (low pressure)
further away from the heart (blood pressure goes…)
down
blood pressure in capillaries
15-35mm Hg (slightly higher pressure)
when do arteries transport de-oxygenated blood
when blood is being pumped from the heart to the lungs
when do veins carry oxygenated blood
pumped from lungs to the heart
renal
kidney
lymphatic system
bringing fat into the bloodstream
subclavian
where lymph system connects to blood stream
-dumped back into
pulmonary
lungs
pulmonary circut
pathway of blood leaving the heart and going to the lungs to pick up oxygen, back to the heart
systemic circut
between the heart and the body
atrium in the hearts
where blood gathers
Vasoconstriction
the process of smooth muscle around arteries contracting and reducing blood flow to tissues
Vasodilation
the relaxing of these smooth muscles for blood flow to increase.
how does blushing work
Blushing is caused by vasodilation in arteries leading to skin capillaries, the body does this since it can release some of the heat produced when the body is nervous.
what causes a pulse
The changes in diameter of the arteries due to heart contractions.
-As the heart pumps blood arteries are able to expand to withstand the sudden high pressure of blood shooting through, when they expand it pulses, and that’s exactly what we can feel
Atherosclerosis
excess lipid forming plaque on the walls of the arteries, causing blot clots that either completely block of arteries causing them to blow, or themselves blow through the walls of the arteries
-heart attack
varicose veins
large volumes of blood distended in the veins, sometimes due to prolonged standing and compression of the veins in the leg.
how does blood get back to the heart through veins
Blood is able to get back to the heart through the veins with valves that exist along the veins. Sequential contractions in the smooth muscle around veins also help massage blood back to the heart.
Are all the capillaries open all the time?
Not all capillaries are open all the time, since if they were the body would need around 200L of blood to properly function filling all those capillaries. Capillaries open depending on what cells in that area need blood.
cardiac output
measurement of the amount of blood that is pumped by the heart each minute
mL/min
cardiac output (formula)
stroke volume x heart rate
stroke volume
the quantity of blood pumped out of the left ventricle with each heartbeat
ml/min
heart rate
number of times the heart beats in one minute
beat/min
average cardiac output
5l/min or 5000ml/min
blood pressure
measurement of the forfce exerted by blood upo0n the walls of arteries
blood pressure is measured by a
sphygmomanometer
average blood pressure
120mmHg
average diastole blood pressure
80mmHg
diastole
blood flowing into artery during ventricular relaxation
sphygmomanometer
a cuff with an air bladder, closes off blood flow through the brachial artery
systolic
pressure exerted ventricular contraction
blood pressure depends on two factors
cardia output and arterial resistance
therefore
-higher heart rate = higher BP
baroreceptors
found in the walls of the aorta and carotid arteries
- detect change in BP, then sends nerve pulses to medulla oblongata
- which then speeds up the heart or slow down the heart
what parts on the heart causes systolic pressure
ventricles
what parts on the heart causes diastolic pressure
ventricles or atrium
hypertension
high blood pressure
where is the oxygen coming from in the capillary
oxygen dissolved in the water (fluid) of the blood
capillary bed
broad term for capillaries, the network
fluid pressure
pushed out by the blood pressure
osmotic pressure
pulling pressure
-pulling of solutes
osmotic pressure explination
water is drawn to higher levels of solvents
high solvents, high osmotic pressure
how does the blood pressure change in the circulatory system
- as it moves away from the left ventricle blood pressure decreases.
- As oxygenated blood leaves the heart it looses blood pressure
albumins
protein created in the liver, responsible for maintaining osmotic pressure
as blood pressure gets further away from your heart
it goes down and down and down
highest blood pressure point
aorta
blood pressure in the arteroles
35mmHg
blood pressure in the venules
15 mmHg
filtration
the selective movement of materials through capillary walls by a pressure gradient
(leaving the blood)
measurement of osmotic pressure
25mmHg
how does fluid move throughout the system
pressure gradient
where higher pressure forces out, lower pressure holds in
lymph system
system of vessels
- returns the fluid to circulatory system (right and left subclavian veins)
- cleans fluid, some in the spleen
- returns blood proteins
- fight infections
what is lymph
fluid that flows through the lymphatic system
swollen lymph nodes
more white blood cells means your fighting something
spleen
holds a ton of blood
opened ended vessels
fluid can enter or empty out of these vessels
lymph vessels
found intertwined with cells
edema
the swelling of tissues, due to low osmotic pressure
-fluid stays in the tissues
starvation
body has run out of glucose, fats and glycogen and starts burning your proteins
less albumins
lower osmotic pressure
shock
body opens up blood vessels (YOU DONT HAVE ENOUGH BLOOD FOR THAT)
-blood pressure drops
anaphylactic shock
everything relaxes, blood pressure drops
what makes the ‘lub’ sound in the heart
pressure from blood flowing from atria into ventricles, causing AV valves to shut
what makes the ‘dub’ sound in the heart
the closing of the semilunar valves, due to presure decrease in the ventricles
myogenic muscle
muscle that can beat on it’s own because nerve and electrical impulses are generated by cardiac muscle
SA node
the hearts tempo or beat rate is set by the SA node
- bundle of specialized nerves
- right upper atrium
AV node
serves as a conductor, sending impulses through two large nerve fibers (purkinie fibers)
-below SA node
purkinje fibers
the two large fibers AV node sends nerve impulses by
-runs through the ventricles
heart rate is influenced by what two
autonomic nerves
- sympathetic
- parasympathetic
sympathetic nervous system
prepares the body for stress
parasympathetic nervous system
returns body to normal resting levels following adjustments to stress
p wave (ECG)
electrical impulse that causes atrial contraction
atrial contraction
occurs at the end of diastole
-initiates rapid flow of blood into the ventricles
wave QRS (ECG)
electrical impulse that causes ventricular contraction
t wave (ECG)
signals ventricles have recovered
arrhythmia
irregular heartbeat
ECG
electrocardiogram
atria
two upper chambers of the heart
when is the lub sound made on the ECG
from Q to R
when is the dub sound made on ECG
wave T
CFE
capillary fluid exchange
process of differences of blood pressure and osmotic pressure moving fluid in and out of tissues
ECF
extracellular fluid
occupies the space between cells and tissues
filtration
fluid moves into tissues
selective movement of materials through capillary walls by a pressure gradient
absorption
fluid moves into capillary
blood takes back the filtrated fluids, osmotic pressure is greater than the blood pressure
fluid pressure
blood pressure witin the blood vessels as blood moves in and out of the heart
osmotic pressure
pressure it takes to exchange fluids across a permeable membrane
“pulling of solutes power”
osmotic pressure is greater than blood pressure
absorption
blood pressure is greater than osmotic pressure
filtration
how does CFE happen
- arteriole blood pressure greater than osmotic pressure
- filtration moves blood plasma out of blood and into ECF
- nutrients and wastes are exchanged with cells in capillary bed
- at venuole osmotic pressure is greater than blood pressure
- absorption takes place and fluid returns into the blood
purpose of capillary
provides cells with oxygen, glucose and amino acids
lymph
is the fluid found in the lymph system vessels from leackage of protein in capillary sites
how is lymph returned to the blood stream
right and left subclavian veins
tachycardia
heartbeat is too fast
-shortness of breath, chest pain, lightheadedness
arrhythmia
issue with rhythme of your heart (chaotic signals from nodes)
-fainting, sweaty, dizziness
angia
heart muscles not getting enough oxygen
-chest pain
heart attack
oxygen is blocked from entering the heart and a portion of the heart stops functioning
cardiac arrest
sudden loss of heart function
difference betwen cardiac arrest and heart attack
cardiac arrest is electrical
heart attack of circulation
heart murmurs
indication of improper blood pumping in the heart (added sound)
aortic aneurysm
buldge in aorta, leading to rupture
-usually caused by high blood pressure or sudden injury
atrial fibrilation
irregulayl fast heartbeat that leads to blood clots
ventricular fibrilation
irregular heartbeat causes chambers to switch
percicarditis and myocarditis
inflamation of the heart muscle
caricose veins
enlarged twisted veins
stroke
build up in arteries leading toward the brain (loss of blood flow to brain)
atherosclerosis
build up of fat in the artery walls
hypertension
high blood pressure
high cholesterol
body has difficulty managing cholesterol (blocked arteries)
pulmonary embolism
blood clot get clogged in the lung artery
coronary arteries
brings oxygen and nutrients to the heart muscle
right ventricle vs left ventricle
left ventricle more circular due to higher blood pressure
right ventrile more cresent due to lower blood pressure
systolic pressure
pressure of the blood on the walls of the arteries as it is pushed out, during contraction
diastolic pressure
pressure of in the blood on the walls of the arteries during resting state, as blood enters the heart in the atrium
numbers for hypertension
> 130/90mm/Hg
numbers for hypotension
<90/60mm/Hg
cardiac output
the volume of blood pumped by each ventricle per minute
ml or L
arteriolar resistance
the resistance to blood flow in the arterioles