Heart & Lungs Flashcards
What is the Bohr effect?
The promotion of oxygen extraction by an increased body temperature.
Outline a deoxygenated RBC’s pathway.
Venules, veins, vena cava, R atrium, tricuspid valve, R ventricle, R semilunar valve, pulmonary artieries, lungs.
What allows for vessels of the peripheral circulatory system to regulate blood flow?
Smooth muscles, which allow them to contract or relax to alter circulation pattern
What is a typical healthy diastole and systole blood pressure?
Diastole - 80. Systole - 120
Which chamber is the strongest? Why?
Left ventricle: pumps to the entire body, where the right ventricle only pumps to the lungs, and atria pump to the ventricles
What are the 3 main components of blood?
RBC’s, WBC’s, plasma.
What is the sinus node?
A small bundle of nerve fibers that controls the hearts rhythm via electrical impulses.
What is hematocrit?
The concentration of RBC’s in your blood.
What branches off of the aorta?
Arteries -> arterioles -> capillaries
What vessels return blood from capillaries to the vena cava?
Venules -> veins
What are the conduction and respiratory zones?
Seperate functional zones of the air passageways
What is the conduction zone?
Structures through which air passes through before gas exchange regions.
Outline the conduction zone and it’s process.
- Nose/mouth - air is filtered and humidified
- Trachea - temperature is adjusted
- L and R bronchii - enters lungs
- Bronchioles -> terminal bronchioles.
What is the respiration zone of the resp. system?
Where gas exchange occurs. The alveolus.
What are the two phases of ventilation?
Inspiration and expiration.
What is internal respiration?
Gas exchange between blood & tissues, and oxygen use by the tissues.
What muscles are involved in ventilation?
Diaphragm, internal intercostals (inspire), external intercostals (expire)
What allows for gas dissusion to occur?
A difference in concentration of CO2 and O2
What effect does exercise have on cardiac output?
Increased heart size.
Larger atria and ventricles - greater volume pumped each beat
Thicker walls - increased contractility (contraction rate)
What effect does exercise have on capillary supply?
A-v O2 difference improves
Better blood flow in capillaries next to muscle fibers (reduces heart attack chance)
Increased capillarization
- Greater surface area and reduced distance between vessels and tissues
- Increased diffusion capacity
- Eased transport of nutrients to cells
What effect does exercise have on blood volume?
Increases volume, along with total RBC count. Achieved through the stimulation of erythropoieses.
What effect does exercise have on ventilation?
Increases to meet the increased demand of gas exchange. Ventilation increses from 6L/min at rest to 150L/min maximal (200L/min voluntary)
Lungs also become more efficient in gas exchange.
What effect does exercise have on oxygen extraction?
Mor gas exchange with increased air flow. Body temperature increases, promoting oxygen extraction. Bohr effect
What are the 4 primary roles of the cardiovascular system?
- Oxygen: lungs -> tissues
- CO2: tissues -> lungs
- Nutrients: digestive system -> other areas
- Waste: Production sites -> excrement sites
What type of muscle is the heart made of?
Smooth muscle
Where is the sinus node?
In the wall of the right atrium
How does the sinus node contract the heart?
Generates an electrical charge called the action potential which travels through the av node and Purkinje fibers
What unit is blood pressure measured in?
mmHg
What is stroke volume? What is a typical stroke volume for a normal person and an athlete?
Amount of blood pumped out of the L ventricle per beat. Typical = 70ml/beat. Athlete = 40ml/beat
What is cardiac output?
Amount of blood pumped into the aorta each minute.
Cardiac output (L/min) = stroke volume x heart rate
What should your maximum heart rate be during exercise?
220 - age
What is the peripheral circulatory system?
Vessels that carry blood (from heart, to tissues muscles and organs, back to heart)
What do capillaries allow for?
Picks up and drops off O2, CO2 and waste products.
Allows for exchange of nutrients
What purpose do valves in veins serve?
They close as blood flows away from the heart so that it does not pool in lower regions.
What pushes blood through veins?
Surrounding smooth mscles and the heart’s pump
What is hemoglobin and how does it work?
Component of RBC comprised of proteins and iron. Each molecule bonds to and transports 4 oxygens
What is PO2 and what does it effect?
Partial pressure of oxygen. It decides how much oxygen the blood carries
What is a-v O2 difference and what does it allowfor?
The difference between oxygen concentration as blood leaves the lungs and when it returns to the lungs. It allows for diffusion into the bloodstream. ml O2/L
What is a typical a-v O2 difference at rest? During exertion?
5mlO2/L, 15mlO2/L
What are new RBC’s called and where are they produced?
Reticulocytes, in the bone marrow.
What is EPO and what does it due.
Erythropoetin, it is a hormone that stimulates RBC formation
What 3 mechanisms are responsible for transporting CO2 to the lungs?
- CO2 combines w/ water to form bicarbonate, which is then transported through the body. (H2CO3)
- CO2 bonds to hemoglobin
- A small amount is dissolved into plasma
What is VO2? VO2 max?
The volume of oxygen consumed in a given time.
The maximal volume supplied and consumed by the body
What 3 things may a difference in a-v O2 (extraction efficiency) be due to?
- More mitochondira
- greater enzyme efficiency
- increased capillarization.
What is the primary role of the respiratory system?
To oxegenate blood and to remove carbon dioxide
What 3 main things compose the resp. system?
Lungs, passageways, muscles
Ventilation, gas exchange and cellular respiration are all forms of respiration. Differentiate between them
- Breathing
- Between lungs & blood / blood and tissues
- Oxygen utilization by the cells.
