the cardiovascular system is considered as?
a closed system of the heart and blood vessels
what pumps blood
the heart
what allows blood to circulate to all parts of the body?
blood vessels
what is the function of the cardiovascular system?
transports oxygen, nutrients, cell wastes, hormones to and from cells
what size is the heart?
big as a human fist
how much does the heart weigh?
less than a pound
where is the heart located at?
in the thoracic cavity, between the lungs in the inferior mediastinum
what is directed toward the left hip and rests on the diaphragm?
Apex
Base points is?
towards right shoulder
a double-walled sac is the?
pericardium
what pericardium is loose and superficial?
fibrous pericardium
what is deep to the fibrous pericardium and composed of two layers?
serous membrane
What pericardium is the outside layer that lines the inner surface of the fibrous pericardium?
parietal pericardium
which pericardium is next to the heart; also known as the epicardium?
Visceral pericardium
what fills the space between the layers of pericardium ( pericardial cavity)?
serous fluid
pericardial cavity is the?
space between the layers of pericardium
Walls of the heart:
Epicardium
Myocardium
Endocardium
what wall of the heart is the outside layer; the visceral pericardium?
Epicardium
what wall of the heart is the middle layer and mostly has cardiac muscle?
Myocardium
What wall of the heart is the inner layer known as endothelium?
Endocardium
which chamber of the heart are the receiving chambers, assist with filling the ventricles, and where blood enters under low pressure?
Right and left Atria
Which chamber of the heart is the discharging chambers, thick-walled pumps of the heart, and during contraction, blood is propelled into circulation?
Right and left ventricles
What vessel in the heart separates the two atria lontudinally
Interatrial septum
What vessel in the heart separates the two ventricles longitudinally?
Interventricular septum
What carries blood away from the heart?
Arteries
What carriers blood towards the blood?
Veins
What side of the heart works as the pulmonary circuit pump?
Right side
what side of the heart works as a systemic circuit pump?
Left side
In pulmonary circulation, blood flows from the right side of the heart to the?
lungs and back to the left side of the heart.
In pulmonary circulation, blood is pumped out of the right side through the pulmonary trunk, which splits into pulmonary arteries and takes?
oxygen-poor blood to the lungs
In pulmonary circulation, oxygen-rich blood returns to the heart from the lungs via?
pulmonary veins
In systemic circulation, Oxygen-rich blood returned to the left side of the heart is pumped out into?
the aorta
In the systemic circulation, after blood is pumped out into the aorta what happens next?
Blood circulates to systemic arteries and to all body tissues
In systemic circulation, how does oxygen-poor blood return to the right atrium?
through the systemic veins, which then empties blood into the superior or inferior vena cava.
Why does the left ventricle have thicker walls?
because it pumps blood to the body through the systemic circuit.
What allows blood to flow in only one direction, to prevent backflow?
Heart valves
Where are the AV (atrioventricular valves) located at?
between atria and ventricles
The left AV valve is the?
bicuspid (mitral) valve
The right AV valve is the?
Tricuspid valve
Where are the semilunar valves located at?
between the ventricle and artery
what are the two semilunar valves?
pulmonary semilunar valve
Aortic semilunar valve
Semilunar valves are what during heart relaxation?
closed
Semilunar valves are what during ventricular contraction?
open
Valves open and close in response to?
pressure changing in the heart
AV valves anchored the cusps in place by?
chordate tendineae to the walls of the ventricles
AV valves open during heart relaxation when?
blood passively fills the chambers
During ventricular contraction, AV valves are?
closed
Blood in the heart does not nourish the?
myocardium
The heart has its own nourishing circulatory system consisting of?
coronary arteries
cardiac veins
coronary sinus
what branches from the aorta to supply the heart muscle with oxygenated blood?
Coronary arteries
What drains the myocardium of blood?
Cardiac veins
What has a large vein on the posterior of the hear; receives blood from cardiac veins
Coronary sinus
Blood empties into the?
right atrium via the coronary sinus
Atrial cells beat how many times per minute?
60 times
Ventricular cells beat how many times per minute?
20-40 times
Which muscle contracts spontaneously and independently of nerve impulses?
Cardiac muscle
What contractions occur in a regular and continuous way?
spontaneous
What are the two systems that regulate the heart activity?
the autonomic nervous system and the intrinsic conduction system (nodal system)
The intrinsic conduction system's main purpose?
sets the heart rhythm
ensures heart muscle depolarizes in one direction only (atria to ventricles)
What is the Intrinsic conduction system composed of?
special nervous tissue
The Intrinsic conduction system (nodal system) enforces a heart rate of how many per minute?
75 beats per minute
The Sinoatrial (SA) Node in the Intrinsic conduction system of the heart is located in the?
right atrium
The Sinoatrial (SA) Node in the Intrinsic conduction system of the heart serves as
a pacemaker
What is at the junction of the atria and ventricles?
Atrioventricular (AV) node
What is in the interventricular septum?
Atrioventricular (AV) bundles / Bundle of His
and
Bundle branches
What spreads within the ventricle wall muscles?
Purkinje fibers
Intrinsic conduction system of the heart first step?
The sinoatrial node (SA node) starts each heartbeat
Intrinsic conduction system of the heart second step?
Impulse spreads through the atria to the AV node
Intrinsic conduction system of the heart's third step?
Atria contracts
Intrinsic conduction system of the heart's fourth step?
At the AV node, the impulse is delayed briefly.
Intrinsic conduction system of the heart's fifth step?
The impulse travels through the AV bundle, bundle branches, and Purkinje fibers
Intrinsic conduction system of the heart sixth step?
Ventricles contract; blood is ejected from the heart.
Rapid heart rate, over 100 beats per minute is considered as?
Tachycardia
slow heart rate, less than 60 beats per minute
Bradycardia
one complete heartbeat, in which both atria and ventricles contract and then relax - this is referred to as.
cardiac cycle
Systole is referred to as?
contraction
Diastole is referred to as?
relaxation
Approximately what is the average heart rate?
75 beats per minute
Cardiac cycle length is normally how many seconds?
0.8 seconds
Atrial diastole (ventricular filling) characteristics
heart is relaxed
pressure in the heart is low
Atrioventricular valves are open
Blood flows passively into the atria and into the ventricles
semilunar valves are closed
Atrial systole characteristics
Ventricles remain in diastole
Atria contract
Blood is forced into the ventricles to complete ventricular filling
Isovolumetric contraction characteristics
Atrial systole ends; ventricular systole begins
Intraventricular pressure rises
AV valves close
For a moment, the ventricles are completely closed chambers
Ventricular systole ( ejection phase ) characteristics
Ventricles continue to contract
Intraventricular pressure now surpasses the pressure in the major arteries leaving the heart.
Semilunar valves open
Blood is ejected from the ventricles
Atria are relaxed and filling with blood
Isovolumetric relaxation characteristics
ventricular diastole begins
pressure falls below that in the major arteries
Semilunar valve close
For another moment, the ventricles are completely closed chambers
When atrial pressure increases above intraventricular pressure, the AV valves open
(Heart sounds) having a longer, louder heart sound caused by the closing of the AV valves is called?
Lub
(Heart sound) short, sharp heart sound caused by the closing of the semilunar valves at the end of ventricular systole is called?
Dup
What is the amount of blood pumped by each side (ventricle) of the heart in 1 minute is called
Cardiac output (CO)
the volume of blood pumped by each ventricle in one contraction (each heartbeat) is called?
Stroke volume (SV)
About how many ml of blood is pumped out of the left ventricle with each heartbeat?
70 ml
What is the typical heart rate? (HR)
75 beats per minute
the product of the heart rate (HR) and the stroke volume (SV) is called?
Cardiac output
how much percent of blood in the ventricles is pumped with each heartbeat?
60
- the critical factor controlling SV is how much cardiac muscle is stretched
- the more cardiac muscle is stretched, the stronger the contraction
This is called?
the Starling's law of the heart
what is the important factor influencing the stretch of the heart muscle?
Venous return
the sympathetic nervous system does what to the heart?
speeds the heart rate
The parasympathetic nervous system, primarily vagus nerve, does what to the heart
slows and steady the heart rate.
Epinephrine and Thyroxine are the hormones that do what to the heart?
it will speed up the heart
Excess or lack of what will modify the heart activity?
Calcium, sodium, and potassium ion
What are the physical factors that affects the heart rate?
age, gender, exercise, body temperature
What are the vessels that carry blood away from the heart?
Arteries and arterioles
what are the vessels that play a role in exchanges between tissue and blood?
Capillary beds
Vessels that return blood toward the heart are?
Venules and veins
What forms a closed vascular system that transports blood to the tissues and back to the heart?
blood vessels
Layers in blood vessels are called?
Tunics
Tunica intima forms a friction-reducing lining
this is called
Endothelium
smooth muscle and elastic tissue
controlled by sympathetic nervous system
which Tunica is this?
Tunica Media
The tunica that forms the protective outermost covering is?
Tunica externa
The tunica is mostly fibrous connective tissue and supports and protects vessels is?
Tunica Externa
What has a heavier, stronger, stretchier tunica media than veins to withstand changes in pressure?
Arteries
What has a thinner tunica media than arteries and operates under lower pressure?
Veins
Veins also have valves to prevent what of blood?
backflow
Capillaries:
only one cell layer thick (tunica intima)
Allows for exchanges between blood and tissue
Form networks called capillary beds that consist of:
-a vascular shunt
- true capillaries
blood flow through a capillary bed is known as?
microcirculation
What branches off a terminal arteriole, empties directly into a postcapillary venule, and entrances to capillary beds that are guarded by precapillary sphincters?
True capillaries
What is the largest artery in the body and leaves from the left ventricle of the heart?
Aorta
what leaves the left ventricle?
Ascending aorta
The aortic arch arches to the?
left
what travels downward through the thorax?
Thoracic aorta
what passes through the diaphragm into the abdominopelvic cavity?
Abdominal aorta
What arteries serve the heart?
the right and left coronary artery
The Brachiocephalic trunk splits into the?
right common carotid artery and right subclavian artery
The left common carotid artery splits into the?
Left internal and external carotid arteries.
The left subclavian artery branches into the?
Vertebral artery and ect....
Intercostal arteries supply the muscles of the?
thorax wall
Other branches of the thoracic aorta supply the?
Lungs
Esophagus
Diaphragm
What is the first branch of the abdominal aorta?
Celiac trunk
The left gastric artery is the?
stomach
The splenic artery is the?
spleen
The common hepatic artery is the?
liver
What supplies most of the small intestine and the first half of the large intestine?
Superior mesenteric artery
The left and right renal arteries are the?
kidneys
The left and right gonadal arteries are the?
Ovarian and Testicular arteries.
Which arteries serve muscles of the abdomen and trunk?
Lumbar arteries
Which artery serves the second half of the large intestine?
Inferior mesenteric artery
what arteries are the final branches of the aorta?
left and right common iliac arteries.
Internal iliac arteries serve the?
pelvic organs
Externa iliac arteries enter the?
thigh -> femoral artery -> popliteal artery -> anterior and posterior tibial arteries.
The superior and inferior vena cava enter the?
right atrium of the heart.
Which vena cava drains the head and arms?
Superior vena cava
Which vena cava drains the lower body?
Inferior vena cava
which vein drains the lateral aspect of the arm?
cephalic vein
What vein drains the medial aspect of the arm and empties into the brachial vein?
Basilic vein
Basilic and cephalic vein are joined as the?
Medial cubital vein (elbow area)
Subclavian vein receives?
Venous blood from the arm via the axillary vein
Venous blood from skin and muscles via external jugular vein
Which vein drains the posterior part of the head?
Vertebral vein
which vein drains the dural sinuses of the brain?
Internal jugular vein
Left and right brachiocephalic veins receive venous blood from the:
Subclavian vein
Vertebral vein
Internal jugular vein
Azygos vein drains the?
thorax
what are the veins that drains the legs?
Anterior and Posterior tibial veins and fibial veins
Which veins receive superficial drainage of the legs?
Great saphenous veins
What vein drains the right ovary in females and the right testicle in males?
right gonadal vein
Which vein empties into the left renal vein?
Left gonadal vein
The left and right renal veins drain the?
kidneys
Which vein drains the digestive organs and travels through the liver before it enters systemic circulation?
Hepatic portal vein
The left and right hepatic veins drain what organ?
the liver
which arteries supply most of the cerebrum?
Anterior and middle cerebral arteries
Which arteries join once within the skull to form the basilar artery?
Vertebral arteries
Which artery serves the brainstem and cerebellum?
Basilar artery.
Posterior cerebral arteries form from the division of the?
Basilar artery
Anterior and posterior blood supplies are united by ?
small communicating arterial banches
small communicating arterial branches results to?
cerebral arterial circle, or circle of Willis
Hepatic portal circulation is formed by?
veins draining the digestive organs, which empty into the hepatic portal vein
Measurements of arterial pulse, blood pressure, respiratory rate, and body temperature is called?
Vital signs
what is an arterial pulse?
a measurement of the heart's contraction rate.
What is blood pressure?
the pressure blood exerts against the inner walls of the blood vessels and the force that causes blood to continue to flow in the blood vessels
pressure in the arteries at the peak of ventricular contraction is called?
systolic pressure
Pressure when ventricles relax is called?
Diastolic pressure.
What is the indirect method of measuring systemic arterial blood pressure, most often in the brachial artery?
Auscultatory method
The amount of blood pumped out of the left ventricle per minute is called?
cardiac output
The amount of friction blood encounters as it flows through vessels is called?
Peripheral resistance
which part of the nervous system has little to no effect on blood pressure?
Parasympathetic nervous system
Which part of the nervous system promotes vasoconstriction which increases blood pressure?
Sympathetic nervous system.
The kidneys regulate blood pressure by?
altering blood volume
What does the kidney do if the blood pressure is too high?
release water in the urine
What do the kidneys do if the blood pressure is too low?
release renin to trigger formation of angiotensin II, a vasoconstrictor.
Angiotensin II stimulates the release of aldosterone which?
enhances sodium (and water) reabsorption by kidneys
a diet low in salt, saturated fats, and cholesterol prevents?
hypertension (high blood pressuree)
Systolic pressure ranges from?
110 to 140 mm Hh
Does diastolic pressure range from?
70 to 80 mm Hg
Hypotension is?
low blood pressure (below 100mm Hg)
Hypertension is?
High blood pressure (140/90 mm Hg)
Substances take various routes entering or leaving the blood
1. direct diffusion through membranes 2. diffusion through intercellular clefts (gaps between cells in the capillary wall)
3. diffusion through pores of fenestrated capillaries
4. Transport via vesicles
what are the two pressure factors that affect fluid movement out of or into a capillary?
Blood pressure and Osmotic pressue
what type of pressure draws fluid into capillaries?
Osmotic pressure
what type of pressure forces fluid and solutes out of capillaries?
Blood Pressure
Blood pressure is HIGHER than osmotic pressure at the?
arterial end of the capillary bed
Blood pressure is LOWER than osmotic pressure at the?
venous end of the capillary bed?
The heart develops as a simple tube and pumps blood by what week of pregnancy?
week 4
The heart becomes a four-chambered organ capable of acting as a double pump over the next how many weeks?
next 3 weeks?
What is the function of the umbilical cord?
carries nutrients and oxygen from maternal blood to fetal blood
fetal wastes move from fetal blood to maternal blood
Which carries nutrient- and oxygen-rich blood to the fetus?
One umbilical vein
Which carries wastes and carbon dioxide-rich blood from the fetus to the placenta?
two umbilical arteries.
What is present in a fetus when bypassing the lungs and liver?
Shunts
Blood entering the right atrium is shunted directly into the left atrium through the?
foramen ovale
what connects the aorta and pulmonary trunk?
Ductus arteriosus
Age-related problems associated with the cardiovascular system include:
weakening of venous valves
varicose veins
progressive arteriosclerosis
hypertension resulting from loss of elasticity of vessels
Coronary artery disease resulting from fatty, calcified deposits in the vessels.