CARDIOVASCULAR SYSTEM Flashcards
A closed system of the heart and blood vessels
Cardiovascular System
What allows blood to circulate to all parts of the body.
Blood vessels
Functions of the Cardiovascular system:
Deliver oxygen and nutrients
Remove carbon dioxide and other waste products
Location of the heart
Thorax between the lungs
Pointed apex directed toward left hip
Is the heart about the size of the fist?
Yes
It is a double serous membrane
Pericardium
A pericardium that is next to heart
Visceral pericardium
A pericardium that is outside the layer
Parietal pericardium
What fills the space between the layers of pericardium?
Serous fluid
Three layers of the heart:
Epicardium, Myocardium, Endocardium
Outside layer; This layer is the parietal pericardium; Connective tissue layer
Epicardium
Middle layer; Mostly cardiac muscle
Myocardium
Inner layer; Endothelium
Endocardium
Four chambers of the heart:
Receiving chambers: Right atrium and Left atrium
Discharging chambers: Right ventricle and Left ventricle
Allow blood to flow in only one direction
Valves of the heart
Four valves of the heart:
Bicuspid valve (left), Tricuspid valve (right), Pulmonary semilunar valve, Aortic semilunar valve
A valve between atria and ventricles
Atrioventricular valves
A valve between ventricle and artery
Semilunar valves
What happens to valve when blood is pumped through?
It opens
Valves are held in place by ____________ or ____________
Chordae tendineae, heart strings
As the blood returns to the heart and fills the atria, what happens to the atrioventricular valves?
They are forced to happen
To prevent backflow of blood to atrium, what happens to the ventricles and atrioventricular valves?
The ventricles contract
The atrioventricular valves closed
As the ventricles contract and filled with blood, what happens to the semilunar valves?
They are forced to open
When the ventricles relax, what happens to the semilunar valve to prevent backflow of blood from atrium to ventricle?
They are forced to close
Associated great vessels of the heart
Aorta, pulmonary arteries, vena cava, pulmonary veins
This vessel leaves the left ventricle
Aorta
This vessel leaves the right ventricle
Pulmonary arteries
This vessel enters the right atrium
Vena cava
This vessel enters left atrium
Pulmonary veins
True or False. Blood in the heart chambers does nourish the myocardium.
False
True or False. The heart has its own nourishing circulatory system.
True
It carries oxygen-rich blood to the heart muscle (myocardium), providing it with the nutrients and oxygen it needs to function.
Coronary arteries
It collects deoxygenated blood from the heart muscle and carry it away.
Cardiac veins
The cardiac veins empty the deoxygenated blood into a large vein called the ___________, which empties the blood into the right atrium.
Coronary sinus
What are the parts of the nourishing circulatory system of the heart?
Coronary arteries, Cardiac veins, Coronary sinus
Heart muscle cells contract, without nerve
impulses, in a regular, continuous way.
Intrinsic conduction system (nodal system)
Special tissues that are involve in the nodal system
Sinoatrial node
Atrioventricular node
Atrioventricular bundle
Bundle branches
Purkinje fibers
It is the pacemaker, which also initiates the contraction of the heart under the nodal system.
Sinoatrial node
SA Node generates the impulse → 2. AV Node delays the impulse → 3. AV Bundle sends the impulse to the bundle branches → 4. Bundle Branches carry the impulse down to the Purkinje fibers → 5. Purkinje Fibers spread the impulse to the ventricles, causing contraction.
Heart Contraction (study figure 11.5)
Systole means __________
Contraction
Diastole means ____________
Relaxation
Events of one complete heart beat
Cardiac Cycle
Blood flows into ventricles
Mid-to-late diastole
Blood pressure builds before ventricle contracts, pushing out blood
Ventricular systole
Atria finish refilling, ventricular pressure is low
Early diastole
Amount of blood pumped by each side of the heart in one minute
Cardiac Output (CO)
Volume of blood pumped by each ventricle in one contraction
Stroke volume
The more that the cardiac muscle is stretched, the stronger the contraction.
Starling’s law of the heart
What is the most common way to change cardiac output.
Changing heart rate
During stress or emergencies, what activates the heart to beat faster?
Sympathetic nervous system
What happens when a body experiences physical and emotional trauma, increased body temperature, exercise, decreased blood volume, and low blood pressure?
Increased heart rate
Two hormones that can increase heart rate:
Epinephrine
Thyroxine
Why there is a need to increased heart rate during exercise?
To supply muscles with oxygen
During rest, what activates the heart to slow heart rate.
Parasympathetic nervous system
What happens to a body when it experiences high blood pressure or blood volume, and decreased venous return?
Decreased heart rate
Parts of the vascular system that takes blood to tissues and back
Arteries, Arterioles, Capillaries, Venules, Veins
Three layers (tunics) of blood vessels:
Tunic intima, Tunic media, Tunic externa
A tunic composed of endothelium
Tunic intima
A tunic composed of smooth muscle and is controlled by the sympathetic NS
Tunic media
This tunic is composed mostly of fibrous connective tissue
Tunic externa
True or Fasle. Walls of the veins are the thickest.
False, it’s the Arteries
True or False. Lumens of veins are longer.
True
What milks blood in veins toward the heart?
Skeletal muscle
True or False. Walls of capillaries are only one cell layer thick to allow for exchanges between blood and tissues.
True
Most arterial blood is pumped by the _________
Heart
What does the veins use to help move blood?
Milking action
Capillary beds consist of two types of vessels:
Vascular shunt, True capillaries
What connects the arteriole to a venule?
Vascular shunt
Known as the exchange vessels
True capillaries
Direction of the diffusion of oxygen and nutrients at the capillary bed.
From blood to tissue cell
Direction of the diffusion of carbon dioxide and metabolic waste products at the capillary bed.
From tissue cell to blood
A process in which the blood, rich in nutrients after absorbing nutrients from the stomach, intestines, pancreas, and spleen, flows through the hepatic portal vein directly to the liver.
Hepatic portal circulation
Oxygenated blood from the mother travels to the fetus through the ______________, which carries oxygen and nutrients to the fetal heart.
Umbilical vein
Known as the pressure wave of blood
Pulse
Pulse is monitored at ___________ where it is easily palpated.
Pressure points
Measurements by health professionals
are made on the pressure in __________________
Large arteries
Pressure at the peak of ventricular contraction
Systolic
Pressure when ventricles relax
Diastolic
Pressure in blood vessels decreases as the distance away from the heart ____________
Increases
Different factors that affect blood pressure
Neural factors, Renal Factors, Temperature, Chemicals, Diet
Autonomic nervous system adjustments (sympathetic division)
Neural factors
Regulation by altering blood volume
Renal factors
Also known as hormonal control
Renin
Heat: Vasodilation effect::Cold:
Vasoconstricting effect
Normal blood pressure
140-110 mm Hg systolic
80-75 mm Hg diastolic
Low systolic (below 110 mm HG); Often associated with illness
Hypotension
High systolic (above 140 mm HG); Can be dangerous if it is chronic
Hypertension
Substances exchanged due to concentration gradients.
Capillary exchange
Where does the direct diffusion during capillary exchange occurs
Plasma membrane
The gaps in capillaries where plasma membrane is not joined by tight junctions.
Intercellular clefts
Also known as pores
Fenestrations
A simple “tube heart” develops in the embryo and pumps by the ______________
Fourth week
The heart becomes a four-chambered organ by the end of
Seven weeks
Few structural changes occur after the
Seventh week
