Circulatory System Flashcards
organisms made up of a small number of cells depend on _ to import/export O2, nutrients, & waster products across cell membranes
diffusion
larger organisms cannot rely on _
diffusion
similar to a citys streets, highways & railways
circulatory system for transport
Humans and other vertabraes have _ circulatory systems
closed
3 things of human circ system
heart, blood vessels, blood that flows through them
heart is enclosed in a sac of tissue called the _
pericardium
thick layer of muscle within heart
myocardium
2 thin layers of _ & _ tissue form a sandwich around myocardium
epithelial & connective tissue
contractions of _ pump blood though circ sys
myocardium
heart beats _ xs per minute
72
_ml of blood in each contraction of heart
70ml
how many years of heart contractions would it take to fill up an Olympic pool?
1 year ( 2 million liters)
the _ divides the right and left sides of the heart
septum
the septum prevents the mixing of _ & _ blood
O2 rich & O2 poor
part of the heart that receives blood
upper chamber/ atrium
pumps blood out of heart
lower chamber/ ventricle
2 pathways of circ sys
pulmonary circulation & systematic circulation
carries blood between heart & lungs
pulmonary circulation
pulmonary circ: in the lungs, _ leaves the blood and O2 is absorbed
CO2
carries blood between heart & the rest of the body
systematic circ
blood that returns to the _ side of the heart is O2 poor bc cells have absorbed much of the
O2 & loaded the blood with CO2
right side
where are the 2 networks of muscle fibers in the heart
1 in the atria, and 1 in the ventricles
when a single fiber in either network of the heart is stimulated, the network (does or does not??) contract as a unit
does contract
where is the SA node located?
the sinoatrial node is located in the right atrium
a small group of cardiac muscle cells
the SA node
pacemaker, aka…
the SA node
impulse spreads from the SA node to the network of fibers in the _
atria
heart:: starting from the beginning, name the path of an impulse
SA node>fibers of atria>atrioventricular node> fibers of ventricles
when the network in the atria contracts, blood in the atria flows where?
into the ventricles
when the muscles in the ventricles contract , where does theblood flow?
outof the heart
names the 3 types of blood vessels
veins, capillaries, arteries
superhighways
arteries
large vessels thatcarry blood from the heartto the tissues of thebody
arteries
all _ carry O2-rich blood,except_?
arteries,except pulmonary arteries
has thick walls to withstand heart pressure
arteries
smallestof the blood vessels
capillaries
side streets & alleys
capillaries
walls are 1 cell thick
capillaries
usually so narrow that blood cells must pass through in single file
capillaries
bring nutrients & O2 to the tissues & takes Co2 & other waste products away
capillaries
return blood to heart
veins
large ones contain valves that keep blood moving toward the heart
veins
force of the blood on the _ is known as BP
Arteries
2 waysof controlling BP
neural and hormonal control
Neural control: neurons detect BP level, sending impulses to _
medulla oblongata
if BP is too high, the ANS releases neurotransmitters that cause smooth muscles to _
relax
if BP is too low, neurotransmitters are released that cause smooth muscles to _
contract
which control elevates bp?
neural
which control lowers bp(reduces blood volume)?
hormonal
_ produced by the heart cause the kidneys to remove waterfrom the blood when bp is high
hormones
sphygmomanometer is used for?
measuring BP
typical bp reading for a healthy person:
120/80
sphygmomanometer: air is pumped into cuff, artery gets blocked, pressure is released and pulse is listened to with a stethoscope,and 2 numbers are recorded. the 1st number is the _ pressure and the 2nd number is the _ pressure
the 1st number is the _systolic pressure and the 2nd number is the diastolic pressure
the force felt in the arteries when the ventricles contract
systolic pressure
the force felt in the arteries when the ventricles relax
dystolic pressure
connective tissue with dissolved substanced and specialized cells
blood
how many liters of blood do people have?
4-6 liters
blood is what % of the bodys total mass?
8 %
blood gets O2 from the _, nutrientsfrom the digestive tracts, and waste products from _
o2 from lungs,waste from body tissue
blood plasma is _% water?
90%
_% blood plasma dissolved: nutrients, enzymes, salts, gasses, hormones, waste products, plasma proteins
10%
3 groups of plasma proteins:
albumins, globulins, & fibrinogen
transport fatty acids, hormones and vitamins/ help to regulate osmotic pressure & blood volume
albumins
transport fatty acids, hormones and vitamins/ some fight viral and bacterial infections
globulins
responsible for the ability of blood to clot
fibrinogen
_ portion of blood consists of redblood cells, white blood cells, and platelets
cellular portion
red blood cells transport:
O2
_ help in the clotting process
platelets
most numerous cells in the blood
redblood cells
1 ml of blood= how many red blood cells?
5 million
gets color from hemoglobin
red blood cells
iron-containing protein that binds to O2
hemoglobin
produced from cells in redbone marrow
red blood cells
red blood cells circulate, and it is how many days before they are worn out>
120 days
red blood cells are worn from:
too much squeezing through narrow capillaries, destroyed in liver and spleen
leukocytes, aka…
white blood cells
do not contain hemoglobin
white blood cells
1000 _ to 1 _
1000 RBC to 1 WBC
produced from bone marrow and contains nuclei
white blood cells
live for days,months, even years
white blood cells
As blood circulates, some fluid leaks from blood into surrounding tissues. how many liters a day?
3L, this helps to maintain movement of nutrients and salt
if leakage of blood went uncheckedm the body would begin to…?
swell with fluid
a network of vessels, nodes, and organs called the _ collects the fluid and returns it back to the circ sys
lymphatic sys
fluid =? _(1 word)
lymph
collectsin lymphatic capillaries & flowsinto larger lymph vessels
lymph
lymph vessels contain valves that prevent lymph from flowing _
backwards
lymph: ducts collect the lymph and return it to the circ sys through 2 openings where?
in the superior vena cava
small, bean-shaped enlargements called:
lymph nodes
act as filters, trapping bacteria & other microorganisms that cause disease
lymph nodes
when large #s of microorganisms are trapped in the lymph nodes,the nodes become…?
enlarged
swollen glands= swollen …
lymph nodes
_ line the intestines & absord fatsoluble vitamins and carry them into the blood
lymph vessels (play a large role in nutrient absorption)
under osmotic pressure from the blood, or contractions of nearby skeletal muscles:::: 2 reasons for _ movements
lymph
mature in the thymus before that can function in the immune system
certain lymphocytes called T cells
the cells that recognize foreign invaders in the body
T cells
helps to cleanse the body and removes damaged blood cells from the circ sys
spleen
harbors phagocytes that engulf & destroy bacteria
spleen
