Heart Structure And Function Flashcards
The compartment labeled “A” in the above diagram is the __ . It receives venous (deoxygenated) blood from the body
Right atrium
The compartment labeled “B” in the above diagram is the___. it contracts to send blood to the lungs for gas exchange
Right ventricle
The compartment labeled “D” in the above diagram is the ___. It
contracts to send blood to the entire body.
Left ventricle
The vessel labeled “E” in the above diagram is the ______. It is the initial conduit for deoxygenated blood to pass to the lungs.
Pulmonary artery
The vessel labeled “F” in the above diagram is the ______. It is the initial conduit for all oxygenated blood to pass to the entire body.
Aorta
The valve labeled “H” is generally called a _______. Don’t worry about left or right on this one. These one-way valves prevent back-flow of blood from adjacent vessels when the bottom chambers relax.
Semilunar valve
. Let’s talk more about the myocardial cells. Cardiac muscle cells are held together, end-to-end, at complex junctions called ________ that consist of interdigitated membrane
Intercalated disks
Within the junctions mentioned in the previous question, the cells are physically tethered by these strong connections that allow force created in one cell to be transferred to the adjacent cell.
Desmosomes
These components of the junctions mentioned in Question 9 allow cardiac muscle cells to be electrically connected. These direct conduits between myocardial cells allow waves of depolarization of to pass rapidly between cells, causing them to contract almost simultaneously
Jap junctions
These specific myocardial cells make up ~99% of the heart, are striated muscle, and have thick and thin filaments organized into sarcomeres
Contractile cells
These specific myocardial cells make up ~1% of the heart, and mostly lack thick and thin filaments. Rather they are specialized for passing electrical signals around the heart.
Autorhythmic cells
This general category of vessel directly returns blood back to the heart atria.
Veins
This general category of vessels directly receives blood from the heart ventricles.
Arteries
These blood vessels are the primary site of vasoconstriction and vasodilation because they contain large amounts of smooth muscle.
Arterioles
These blood vessels are where gas, nutrient, and waste exchange occurs in body tissues.
Capillary
These blood vessels receive deoxygenated blood from the vessels named in the previous question.
Venules
The circuit of the cardiovascular system that conducts deoxygenated blood from the heart to the lungs and returns oxygenated blood back to the heart is called the _______.
Pulmonary circuit
The circuit of the cardiovascular system that conducts oxygenated blood from the heart to body tissues and returns deoxygenated blood back to the heart is called the _______
Systemic circuit
______ defines the amount of blood that is pumped by one ventricle during a single contraction
Stroke volume
______ is a term that describes all the electrical and physical events that happen in the heart during one contraction-relaxation cycle.
Cardiac cycle
If we count the number of contraction – relaxation cycles that happen in 1 minute, that defines a person’s _______
Heart rate
The volume of blood entering the heart from the venous circulation at any given moment is technically called ______
Venous return
______ defines the volume of blood left in a ventricle at the end of its contraction phase.
End systolic
______ defines the maximum amount of blood that a ventricle can hold when it is fully relaxed.
End diastolic
______ describes the time when a heart chamber (atria or ventricles) are contracting and pumping blood.
Systole
______ describes the time when a heart chamber (atria or ventricles) are relaxing and filling with blood.
Diastole
This concept explains that the heart must pump all the blood that returns to it AND theforce of heart contraction is determined by the volume of blood returning to it at any given moment.
Frank starling law
The total volume of blood pumped by one ventricle during a given period of time ( usually 1 minute) is called
Cardiac output
These blood vessels have the smallest diameter. They are also the site of exchange for nutrients, wastes, and signal molecules between the blood and body tissues since they are composed only of a single layer of loosely connected endothelial cells.
Capillaries
These blood vessels deliver blood to specific tissues and the smooth muscle cells embedded in their walls give them variable resistance. These characteristics make them ideal for fine tuning blood flow to meet the metabolic demands of different tissues around the body.
Arterioles
These blood vessels collect blood just after it has had a chance to exchange nutrients, wastes, and signal molecules with body tissues and start its return journey to the heart.
Venules
These blood vessels have the widest diameters and therefore hold more than half of the blood in our bodies. They also typically run close to the surface of our skin, so they must have both fibrous tissue for strength and elastic tissue for flexibility.
Veins
These blood vessels are structurally reinforced with elastic and fibrous tissue, since they must withstand the highest blood pressures.
Arteries
When considering blood pressure, two values are always recorded. The ________ pressure represents the maximum pressure that occurs in an artery near the heart and follows ventricular contraction.
Systolic
The ________ pressure represents the minimum pressure in an artery near the heart and coincides with ventricular relaxatio
Diastolic
There are three main factors that determine your blood pressure at any given moment (i.e., when resting, exercising, etc.). One factor, referred to as _______, focuses on how hard your heart is working at that moment. This factor combines the number of beats per minute and the volume of blood pumped per ventricular contraction, both of which are controlled by autonomic efferent pathways.
Cardiac output
Another key factor in determining blood pressure is the water content of the blood plasma. This factor is referred to as _______ and is regulated primarily by the kidneys with guidance from both autonomic and hormonal efferent pathways
Total blood volume
A third factor that influences your blood pressure, called ________, is determined by the variable diameter (or radius) of the arterioles. This factor is mostly under tonic sympathetic control and strategically diverts more blood flow to hard-working areas and sends less blood flow to less-essential organs at any given time.
Total peripheral resistance