Circulatory System Flashcards
What is a circulatory system?
how organisms deliver oxygen and nutrients to tissues
What is simple diffusion?
passive movement of dissolved substances due to concentration gradient
List the organisms that do not have circulatory systems:
- kingdom archaea
- kingdom eubacteria
- kingdom protista
- kindgom fungi
- Kingdom animalia
1) porifera
2) cnidaria
3) platyhelminthes
4) nematoda
5) rotifera
How is hemolymph pumped in an insects body?
tubular hearts pump fluid through a single dorsal vessel–> sinuses–> hemocoel
How does hemolymph re-enter a relaxed insect heart?
ostia
___ allow air to pass into the tracheal system of insects
spiracles
list the invertebrate animals with an open circulatory system:
Kingdom Animalia
1) mollusca
2) arthropoda
3) echinodermata
___ is fluid that allows gas exchange in closed circulatory systems
blood
List the invertebrates with a closed circulatory system:
annelida (segmented worms)
What are the primary/true heart chambers?
atria and ventricles
2 chambered hearts have 2 chambers-What are they?
1 atrium, 1 ventricle
2 chambered hearts only pump ___ blood
deoxygenated
2 chambered hearts are ___ circulation hearts
single
What is a common example of an organism that has a 2 chambered heart?
fish
Ventricles are (stronger/weaker) than atria
stronger
3 chambered hearts have 3 primary chamber- What are they?
right and left atrium; single ventricle
3 chambered hearts mix deoxygenated and oxygenated blood in the ___
ventricle
3 chambered hearts are ___ circulation hearts
double
What types of animals have 3 chambered hearts?
poikilothermic amphibians and reptiles
4 chambered hearts have 4 primary chambers-what are they?
left and right atrium; left and right ventricle
4 chambered hearts pump both deoxygenated and oxygenated blood without ___
mixing the deoxygenated blood and oxygenated blood
4 chambered hearts are ___ circulation hearts
double
What type of animals have 4 chambered hearts?
bird and humans (homeothermic)
the right atrium accepts ___ blood from vena cava
deoxygenated
blood pump from the right atrium ___, through the ____
right ventricle; tricuspid valve
What is the atrioventricular valve with 3 cusps?
tricuspid valve
What are the largest veins?
Vena cava
connect to the right atrium
What returns deoxygenated blood from above the heart?
Superior Vena Cava
What returns deoxygenated blood from below the heart?
inferior vena cava
What prevent back-flow fro the ventricles to the atria?
Atrioventricular valves (AV valves)
AV valves close when what contracts?
papillary muscles
What are the stringy tendons that attach papillary muscles to AV valves
chord tendineae
The right ventricle pumps deoxygenated blood–> pulmonary arteries through what valve?
pulmonary semilunar valve
Semilunar valves have ___ cusps
3
__ valves ensure one-way flow of blood from ventricles to arteries?
semilunar
the __ take deoxygenated blood from the right ventricle to the lungs for gas exchange
pulmonary arteries
What are the vessels moving away from the heart?
arteries
__ return oxygenated blood to the left atrium after gas exchange at the lungs
pulmonary veins
What are the vessels that carry blood toward the heart?
veins
oxygenated blood flows from the left atrium to the left ventricle, through the ___
bicuspid/mitral valve
the bicuspid/mitral valve (AV) valve has __ to ensure unidirectional blood from the left atrium to left ventricle
2 cusps/flaps
the __ is the most muscular chamber of the heart
left ventricle
the left ventricle forcefully ejects oxygenated blood through the __ valve–> __
aortic semilunar; aorta
the __ is the largest artery
aorta
the aorta leaves from the
left ventricle
the aorta has the highest __ of any vessel
blood pressure
what are the 2 circulation of the human cardiac system?
pulmonary; systemic
__ circulation moves deoxygenated blood to the lung for oxygenation
pulmonary
__ circulation moves oxygenated blood to the body tissues
systemic
does systemic or pulmonary circulation have a higher resistance to blood flow?
systemic
how does the heart pump blood to itself?
coronary circulation
What is the muscular layer of the heart?
myocardium
What are the cells contained in the myocardium?
cardiomyocyctes
What type of cells line the inside of the heart?
endothelial
the __ lies beneath the myocardium
endocardium
__ drain deoxygenated blood from the myocardium to the right atrium via the coronary sinus
cardiac veins
What is the small opening in the right atrium that cardiac veins empty into?
coronary sinus
the __ is a protective sack of fluid surrounding the heart
Pericardium
what is the fluid in the pericardium?
serous pericardium
cardiomyocytes have automaticity- what does that mean?
action potentials will generate without external nerves having to initiate the action potential
the __ is the pacemaker of the heart
sinoatrial node (SA node)
the SA node has the greatest __ in the heart
automaticity
where is the SA node located?
right atrium
even though the heart can function completely independently, beating pace is influenced by __ (faster) & __ (slower)
sympathetic, parasympathetic
the __ extends from the medulla oblongata and innervates the SA node
parasympathetic vagus never
the parasympathetic vagus nerve sends a default signal to __ the SA node automaticity to ___
slow; 60-90 BPM
what is a tachycardic heart rate?
> 100 BPM
what is a bradycardic heart rate?
<60 BPM
What is the function of the AV node?
add a brief delay between atrial and ventricular contractions
Where does the AV node conduct to?
bundle of His
Where is the bundle of His located?
inter-ventricular septum
What does the bundle of His do?
carries the signal to the base of the heart
purkinje fibers are located in the walls of the __
ventricles
__ receive conduction from the bundle of His
purkinje fibers
what is the name for the period of time right after the ventricles eject their blood?
systole
systole is the phase were blood pressure is __
the highest
What is the period of time right after the atria contract to fill the ventricles?
diastole
the myocardium is __ during diastole
relaxed
diastole is the phase where blood pressure is the __
lowest
atria are relaxed during the __ heart sound
“lub”
__ are contracting during the “lub” heart sound
ventricles
__ are contracting during the “dub” heart sound
atria
ventricles are relaxed during the __ heart sound
“dub”
When does sytole occur (sounds)?
between lub and dub
When does diastole occur (sounds)?
after dub (before next lub)
Which side of the heart is stronger
-left or right?
left
Why is the left side of the heart stronger than the right side?
systemic circulation and greater vascular resistance
__ are contact points between adjacent cardiomyocytes
intercalated discs
__ ‘stitch’ cardiomyocytes together at intercalated disks
desmosome
__ are protein tunnels that connect adjacent caridomyocytes
gap junctions
gap junctions are involved with __ transport
molecule/ion
__ allows the heart to function in unity
cardiac syncytium
What is the wave that represents both atria depolarizing?
p wave
what is the wave that depicts depolarization through the inter ventricular septum
q wave
the q wave initiates ___
ventricular depolarization
what is the wave that represents depolarization through both ventricles?
r wave
what is the wave that represents completion of ventricular depolarization
s wave
the __ shows the entirety of ventricular depolarization
qrs complex
what is the wave that represents ventricular re-polarization?
t wave
what are refractory cells?
cells that are too hyper-polarized for another action potential to occur
What is heart rate (HR)?
is how fast or slow the heart beats
__ is the volume of blood pumped fro the heart with each beat?
stroke volume (SV)
true or false- the left and right ventricle pump equal amounts of blood
true
what is end-systolic volume (ESV)?
the amount of blood in ventricles after contraction
what is end-diastolic volume (EDV)?
the amount of blood in ventricles before contraction
how do you calculate stroke volume (SV)?
subtract ESV from EDV
what is cardiac output (CO)?
volume of blood pumped by the heart per minute
How do we calculate cardiac output?
CO= HR x SV
what is total peripheral resistance (TPR)?
vascular resistance to blood flow
how does vasoconstriction change TPR?
increases it
how does vasodilation change TPR?
decreases it
__ is the highest arterial pressure that occurs during systole
systolic blood pressure (SBP)
__ is the lowest arterial pressure that occurs during diastole
diastolic blood pressure (DBP)
__ is the average arterial pressure during one complete cardiac cycle
mean arterial pressure (MAP)
mean arterial pressure (MAP) is a better indicator of cardiovascular health than __
SBP or DBP
equation for mean arterial pressure (MAP)
MAP= CO x TPR
__ is the technique where a stethoscope and sphygmomanometer are used to measure SBP and DBP
auscultation
what do blood vessels do?
transport blood to and from the heart in a closed circulatory system
how many layers are there in blood vessels
3
what are the 3 blood vessel layers (arteries and veins)- from superficial to most deep
tunica extern; tunica media; tunica intima
the tunica __ is the innermost vessel layer
intima
the tunica intimate is made of __ cells
endothelial
the tunica __ reduces friction to blood floow
intima
the __ lies between the tunica intimate and tunica externa
tunica media
the tunica media contains __ for vasoconstriction/vasodilation
smooth muscle
the tunica externa is the __ vessel layer
outermost
the tunica externa contains __ & __ proteins, as well as __ fibers
collagen; elastin; nerve
what are the most elastic vessels
arteries and arterioles
arteries and arterioles hold __ blood than other vessels
less
which vessels have the greatest drop in blood pressure?
arterioles (resistance vessels)
where does the elasticity of arteries and artioles come from?
thick smooth muscle in the tunica media; high amount of elastin in tunica externa
What is the main role of arteries and arterioles
carry blood away from the heart
usually oxygenated blood to body tissues
which arteries carry deoxygenated blood away rom the heart?
pulmonary and umbilical arteries
vasoconstriction and vasodilation occurs in response to..?
hormone and thermoregulation
__ are the smallest diameter vessel, which are found between arteries and veins
capillaries
how thick are capillary walls?
one endothelial cell thick (tunica intima only)
what are fenestra in capillaries?
pores for diffusion
capillaries bring __ & __ to body tissues
nutrients; oxygen
capillaries remove wastes like __ & __ from body tissues
CO2, urea
why is plasma forces out of the arterial end of a capillary?
hydrostatic pressure is high
why is plasma taken-up at the venous end of a capillary?
osmotic/colloid pressure is high
__ connect capillaries to the veins
venules
veins are __ than arteries, which allows them to hold more __
wide;blood
do venues and veins contain smooth muscle?
yes, but not as much s arteries or arterioles
why are veins sometimes referred to as capacitance vessels?
most of the body’s blood is found in veins
BP is lowest in the __ (Vessels)
veins
why do veins contain valves?
ensure blood is flowing toward the heart
what pumps do veins use to make sure blood reaches the heart?
skeletal muscle pump and respiratory pump
in the __, working muscles squeeze veins to move blood forward
skeletal muscle pump
in the __, pressure changes during breathing squeeze veins to move blood toward the heart
respiratory pump (abdominothoracic pump)
what are portal systems?
capillary bed connected to another capillary bed by a portal vein
describe the benefit of the hypophyseal portal system
hormones quickly travel directly from the hypothalamus to the anterior pituitary
the blood clotting cascade is a __ feedback mechanism
positive
describe the blood clotting cascade in general terms
damaged tissue attracts platelets, which attract more platelets until a clot is achieved
__ is an important element in the manufacture of many clotting factors, including prothrombin
vitamin K
how are forms of vitamin K modified and produced?
symbiotic bacteria in the large intestine
blood is found in animals with __ circulatory systems
closed
what are the 3 general components of blood
plasma; small portion of leukocytes (WBCs) and platelets, and erythrocytes (RBCs)
what are the components of plasma?
water; proteins; nutrients; hormones
__ (thrombocytes) are cell fragments that do not contain a nucleus
platelets
cells that do not contain a nucleus are __
anucleate
megakaryocytic are large __ cells
bone marrow
__ are a precursor to platelets, which are involved in the clotting cascade
megakaryocytes
erythrocytes (RBCs) contain millions of __, which can hold dup to __ O2 each
hemoglobin; 4
erythrocytes are __ (no nucleus)
anucleate
erythrocytes contain __ on their surface
antigens
what are antigens?
little sugars and proteins that mark out blood cells as a certain type
what antigens are present on erythrocytes for each of the 4 blood groups?
Type A- A antigen
Type B- B antigen
Type AB- both A and B antigens
Type O- no A or B antigen
what do antibodies do?
allow our immune system to find foreign antiboides
what does the rhesus factor (Rh) do?
gives +/- blood types
+ if antigens are present
-if no Rh antigens
if a donor is Rh +, they cannot donate to someone who..
is Rh-
eight blood types
A+ and A-
B+ and B-
AB+ and AB-
O+ and O-
What blood type is the universal donor?
O-
no RBC surface antigens
What blood type is the universal acceptor?
AB+
has all RBC surface antigens
the __ is a highly vascularized organ in the uterus
placenta
the placenta provides oxygen and nutrient to the fetus through the
umbilical cord
the __ carries oxygenated blood from the placenta to the fetus
umbilical vein
the __ allows some oxygenated blood from the umbilical vein to flow into the inferior vena cava
ductus venosus
does the maternal and fetal blood mix across the placenta?
no, embryonic chorion protects against blood mixing
erythroblastosis fetalis
Rh- mother gives birth to a Rh+ baby
blood mixing causes mother to develop antibodies against RH antigens (Rh+ blood)
If Rh- mother gets pregnant with another Rh+, anti-Rh antibodies cross the embryonic chorion and cause hemolysis in the Rh+ baby
baby is born as an anemic
__ are leaky vessels that take-up fluid that was not re-absorbed by the capillary bed
lymphatic capillaries
what is the fluid in the lymphatic system called?
lymph
what does lymph contain?
interstitial fluid, bacteria, fats, and proteins
what are the lymphatic capillaries that absorb fats in the villi of the small intestine?
lacteal
__ are small finger like projections that increase the surface area in the small intestine
villi
__ contain immune cells that inspect the lymph
lymph nodes
lymphatic veins are not connected to the __
heart
lymphatic veins connect to __ of the circulatory system, which then connect to the heart
veins
does the lymphatic system have a central pump
no; it is a low pressure system and uses the skeletal muscle pump (like veins)
