Chapter 1G - Cardiopulm Anatomy and Physiology Flashcards
The heart muscle is called what?
Where do the left and right atriums deliver blood?
What does ventricle contraction produce the force necessary to do?
What are the names of the atrioventricular valves? What do they do?
What are the semilunar valves and what do they do?
The heart muscle is called the myocardium.
The left and right atriums bring blood to the left and right ventricles.
Ventricles produce the force necessary to eject blood out of the heart into circulation.
The tricuspid valve and mitral valve form the AV valves. During ventricular contraction (systole) the AV valves prevent blood from flowing back into the atria.
The aortic valve and the pulmonary form the semilunar valves. During ventricular relaxation (diastole), the semilunar valves prevent backflow from the aorta and pulmonary arteries into the ventricles.
Explain Systole and diastolic meaning with BP.
Systole is the highest pressure and the top number recorded in a BP reading.
Represents the pressure exerted by the blood on the walls of the blood vessels. Occurs during the contractile phase of the cardiac cycle, which forces oxygenated blood into the body and blood into the pulmonary arteries to be oxygenated.
During diastole, the heart chambers relax and fill with blood, this is the lowest pressure and bottom number in the BP measurement.
Explain the electrical conduction system for the heart? SA node and order to what follows.
Mechanical contraction of the heart is controlled by a conduction system. Causes the contraction and recovery of atria and ventricles.
SA node is the intrinsic pacemaker, normally the initiator of rhythmic electrical impulses. Located in upper wall of the right atrium.
Internodal pathways conduct impulses from SA to AV node, which is where the location where the electrical impulses is slightly delayed before passing to the ventricles. The AV bundle conducts the electrical impulse to the ventricles, and it is divided into right and left branches. Bundle branches divide into purkinje fibers, which transmit the impulse throughout the ventricles.
Explain the regulation of the electrical activity of the heart?
What is the ANS responsible for? Tachycardia vs bradycardia? Sympathetic vs parasympathetic?
The ANS is responsible for the rhythmicity and conduction properties of the myocardium. Atria has parasympathetic and sympathetic fibers, while the ventricles have mostly sympathetic fibers.
Sympathetic fibers increase the speed of SA node depolarization, increase heart rate - tachycardia. Parasympathetic fibers decrease speed of SA node depolarization, leading to bradycardia
How are we measuring the electrical activity of the heart with an ECG (Electrocardiogram)? PQRST?
An ECG Electrocardiogram represents the heart’s electrical changes during the cardiac cycle. The cycle consists of several waves that represent depolarization and repolarization of the atria and ventricles.
First wave is P-wave - corresponds to atria depolarization, which causes contraction of atria and the movement of blood to ventricles
Depolarization of ventricles is QRS complex - ventricle contraction, which produces the force to send blood pulmonary and peripheral blood vessels.
T wave is ventricular repolarization, which can be thought of as the recovery from depolarization.
Note: Atria will repolarize during the QRS, and is masked by the QRS in an ECG.
Explain the vascular system, with arteries vs veins with blood direction.
Which has stronger walls between arteries in veins, why?
Can arterioles constrict completely and/or dilate?
What are capillaries for?
Arteries - Carries blood away from heart and the blood returns via the venous system.
Arteries have strong walls as blood moves quickly through them. Arterioles control flow of blood in capillaries. Arterioles have strong muscular walls that can constrict, close completely, or become dilated, effectively controlling the flow of blood into the capillaries.
Capillaries are point of exchange for nutrients, hormones, oxygen, fluids, and electrolytes between the blood and the interstitial fluid of body tissues.
Explain the vascular system, focusing on venous and veins.
How does hemoglobin control the rate of chemical reactions in the body.
Blood from the capillaries is collected by venules that converge into veins and return the blood to the heart. Veins are thin but muscular in thier walls and can constrict or dilate. Some veins in legs have valves to prevent backflow.
Vascular system (which includes arteries and veins) transports oxygen and removes carbon dioxide waste and brings it to the lungs. RBC transports oxygen via hemoglobin, an iron protein molecule.
Hemoglobin also controls the rate of chemical reactions in cells by regulating hydrogen ion concentration.
What is blood doping? Is it legal in most sport organizations?
Banned by most sport organizations, practice of artificially increasing the number of RBC to increase max oxygen uptake and increase athletic performance. Has health risks.
Explain the respiratory system and its function with oxygen and CO2?
Explain the path air takes to end in the alveoli. Put in order.. alveoli, left/right bronchi, trachea, bronchioles.
How many divisions of bronchioles are there, roughly?
The respiratory system exchanges oxygen and carbon dioxide.
Air first goes through nasal cavity where it is purified, warmed and humidified. Air then goes to the lungs via the trachea (first generation respiratory passage), the right/left bronchi (second generation) and the bronchioles (third generation). The bronchioles continue to divide for approx 23 generations down to the small alveoli, where gas is exchanged during respiration.
Explain what the diaphragm does during regular inspiration/expiration.
During relaxed breathing, the contraction of the diaphragm during inspiration creates a negative pressure vacuum, drawing air into the lungs. The relaxation of the diaphragm causes an elastic recoil of the lungs and the chest wall compresses the lungs, causing air to be expelled.
During inspiration the diaphragm moves down, expiration the diaphragm moves up.
Heavy breathing requires activation of which muscles, due to the extra force? Is expiration passive always?
Is expiration passive at rest?
Heavy breathing requires movement of the ribs to allow for expansion of the lungs.
The ribs are elevated by muscles (external intercostals, SCM, anterior serratus, and scalenes) during inspiration.
The abdominal muscles and internal intercostals depress the chest during expiration.
Expiration during resting conditions is passive but requires muscular contraction during exercise.
The walls of the lungs are composed of several layers of membranes called? What is pleura, pleural pressure and pneumothorax?
Pleura - membranes on the wall of the lungs, that are composed of several layers
Pleural pressure refers to the slightly negative pressure in the small spaces between the chest wall and lung pleura that enhances inspiration.
Pleural pressure that is equal to or higher than atmospheric pressure will cause the lungs to collapse in a dangerous condition called pneumothorax.
Explain alveoli pressure and how it’s important for inspiration and expiration.
How does this relate to oxygen and co2
When the glottis is open, no air moves in or out of the lungs, and the pressure inside the alveoli is reffered to as alveolar pressure. This pressure must be below atmospheric pressure for inspiration to occur and expiration requires alveoli pressure to be higher than atmospheric pressure.
The exchange of respiratory gases occurs when oxygen diffuses from the alveoli into pulmonary blood and carbon dioxide diffuses from blood into the alveoli.’
Explain diffusion amongst oxygen and Co2 involving concentration gradient.
Diffusion of oxygen and CO2 across cell membrane s works according to a concentration gradient, where gas molecules move from regions of higher gas concentrations to a region of lower concentration.
Explain the valsalva maneuver. What can the valsalva maneuver lead to if pressure is too high?
Results from abdominal muscle contraction with the diaphragm when the glottis is closed, causing an increase in intra-abdominal pressure during heavy weightlifting.
This is thought to help stabilize the core and spine. If the muscle contraction is too forceful, can cause a hernia.
