Heart And Lungs Flashcards
Structure of the heart
Superior and inferior vena cava, right atrium, tricuspid valve, right ventricle, aortic valve, pulmonary arteries, lungs, pulmonary veins, left atrium, bicuspid valve, left ventricle, aortic valve, aorta, arteries, capillaries, veins … Repeat
Blood pressure types
Systole: pressure in the ventricles when they contract and push blood into the body (120 mm Hg)
Diastole: pressure in the heart when it is in relaxation phase of cardiac cycle (70-80 mm Hg) pressure of peripheral BP outside of heart
Cardiac output
The amount of blood that is pumped into the aorta each minute. Measured in litres per minutes.
Q=stroke volume x heart rate
Quantity of blood that flows to the peripheral circulation
Stroke volume
The amount of blood that is pumped out of the left ventricle with each heart beat. Measured in mm (70 ml of blood)
Heart rate
The number of times the heart beats per minute. Measured in beats per minute (40bpm for trained athlete, 70bpm for normal person)
Maximum heart rate
220 - age
Arteries, arterioles, capillaries
Carry blood away from heart, branch into smaller vessels, width of 1 red blood cell. Capillaries are composed of endothelial cells that allow exchange of oxygen and nurturers from blood, to muscles and organs, and also allow blood to pick up waste products and carbon dioxide from metabolism.
Veins, venules, valves
Capillaries connect to form larger and larger vessels (venules). They merge to veins, which returns the blood to the heart. Valves open with flow of blood in direction to heart.
Red blood cells
Also called erythrocytes. Primary role is to transport oxygen from lungs to tissues and carbon dioxide from body back to lungs.
Hematocrit
The percentage of red blood cells that makes up the blood, about 45%.
Hemoglobin
Oxygen binding substance that allows red blood cells to transport oxygen from the lungs to the tissues, and carbon dioxide from body back to lungs.
Can transport 4 oxygen molecules.
Partial pressure of oxygen
PO2
The amount of oxygen that is carried by the blood. High=hemoglobin binds easily to oxygen. Low=oxygen unbinds from hemoglobin and is diffused to tissues to be used to produce energy.
Arterial-venous oxygen difference
a-vO2 difference
Difference in amount of oxygen present in blood when leaving lungs and amount of oxygen present in blood when returning to lungs. Measured in mm of O2 per decilitre of blood (ml O2/100ml of blood)
Action potential
An electrical charge that causes the the muscle walls of the heart to contract.
Reticulocytes
New red blood cells that are made in the bone marrow
Erythropoietin (EPO)
The principal factor that simulates red blood cell formation in this hormone. EPO increases from exercise.
Oxygen uptake
Amount of oxygen that’s consumed by the body due to aerobic metabolism. Increases in relation to amount of energy needed to perform an activity.
VO2
Volume of oxygen (in litres) that is consumed in a given amount of time, usually 1 minute.
Maximal aerobic power
VO2 max
The body has a limit on the amount of oxygen it can consume. This is the way to evaluate the maximum volume of oxygen that can be supplied to and consumed by the body.
Conduction zone
Passage way of respiratory system. Anatomical structures which the air passes before reaching respiratory zone (nose/mouth, trachea, right and left bronchi, bronchioles, terminal bronchioles) known as “respiration tree”
Respiration zone
Bronchioles branch into this zone; the region where gas exchange occurs. Tiny air sacs in the lungs, alveoli, are responsible for gas exchange.
Human respiration
- Ventilation or breathing (inspiration and expiration)
- Gas exchange
- Oxygen utilization by the tissues for cellular respiration.
Gas diffusion
Diffusion in the movement of molecules from a higher concentration to a lower concentration (oxygen in air diffuses through alveolar membrane into deoxygenated pulmonary capillaries).
Blood volume
Shown to increase with training as the number of red blood cells increases through simulation of erythropoiesis.
Bohr effect (an exercise training effect)
During exercise, body temperature increases, which in turn promotes oxygen extraction. This describes the reduced effectiveness of hemoglobin to hold oxygen.
Altitude
Density of molecules in air changes at altitude (“thin air”). Person must breathe more and deeper (hyperventilation) to get the amount or volume of oxygen required.
Acute mountain sickness (AMS)
With changes in altitude, body cannot always adequately adapt, so AMS occurs. Symptoms=headache, vomiting, breathlessness, exhaustion, even death
Right and left ventricles
Right ventricle: receives deoxygenated blood and pumps it to the lungs
Left ventricle: receives oxygenated blood from the lungs and pumps it to the body (bigger)
Right and left atrium
Right atrium: receives blood from the body and pumps it to the right ventricle
Left atrium: receives blood from lungs and pumps it to the left ventricle
Sinus node
Small bundles of nerve fibres found in wall of right atrium that generate an electrical impulse (heart beat). Determines how much the heart needs to pump.
Peripheral circulatory system
Carries blood away from the heart to the muscles and organs, then returns the blood back to the heart
Transport if CO2
3 ways
- Small amount is dissolved in blood plasma
- CO2 bonds to the hemoglobin molecule
- CO2 combines with water to firm biocarbonate molecules to be transported through the body
How does the body accumulate to to altitude?
As body gets use to altitude & low pressure, the HR, breathing rate and production of RBC increases. Allows more oxygen to be “grabbed”. Breaks should be taken every 2000-4000 ft.
High altitude cerebral edema
(HACE)
High altitude pulmonary edema
(HAPE)
HACE= Affects the brain, and causes sever swelling
HAPE= affects blood flow through lungs, fluid build up in lungs
