Cardiovascular System Overview
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Questions and Answers

What is the primary function of capillaries in the cardiovascular system?

  • To regulate blood flow through arterioles
  • To store deoxygenated blood
  • To enable the exchange of gases and nutrients between blood and tissues (correct)
  • To transport oxygen-rich blood to the heart

Arteries always carry deoxygenated blood, making them unique among blood vessels.

False (B)

What compound produced during muscular contraction is a potent stimulator of blood flow?

nitric oxide

The smallest blood vessels that facilitate gas exchange are called __________.

<p>capillaries</p> Signup and view all the answers

Match the following types of blood vessels with their primary functions:

<p>Arteries = Carry oxygen-rich blood away from the heart Veins = Return deoxygenated blood to the heart Arterioles = Primary site of vascular resistance Capillaries = Enable nutrient and gas exchange</p> Signup and view all the answers

Which statement accurately describes arterioles?

<p>They branch out from arteries and lead to capillaries. (C)</p> Signup and view all the answers

The process of diffusion allows oxygen to move from areas of lower concentration to areas of higher concentration.

<p>False (B)</p> Signup and view all the answers

How long would a line of all the capillaries in one person approximately be?

<p>more than 40,000 kilometres</p> Signup and view all the answers

Which of the following are characteristics of asthma?

<p>All of the above (D)</p> Signup and view all the answers

Chronic obstructive pulmonary disease (COPD) is a condition that can be effectively treated in the same way as asthma.

<p>False (B)</p> Signup and view all the answers

What is the term used to describe shortness of breath?

<p>Dyspnea</p> Signup and view all the answers

The amount of oxygen taken up and consumed by the body in metabolic processes is called _________ __________.

<p>oxygen consumption</p> Signup and view all the answers

Oxygen consumption (VO2) decreases as the workload increases.

<p>False (B)</p> Signup and view all the answers

Match the following terms related to oxygen consumption with their descriptions:

<p>VO2 = The amount of oxygen inspired minus the amount of oxygen expired Q = Cardiac output, representing total blood flow throughout the body Indirect calorimetry = A method to determine oxygen consumption using a computerized metabolic cart system VO2max = The maximum rate of oxygen consumption</p> Signup and view all the answers

What happens to blood flow to less active organs during exercise?

<p>It decreases (C)</p> Signup and view all the answers

The brain's blood flow distribution remains unchanged during exercise.

<p>True (A)</p> Signup and view all the answers

What structural changes occur in the heart due to prolonged aerobic training?

<p>Increased ventricular volume and thickness of the ventricle walls.</p> Signup and view all the answers

Aerobic exercise leads to improvements in the efficiency of the __________ system.

<p>cardiovascular</p> Signup and view all the answers

Match the following terms with their descriptions:

<p>Q = Cardiac output SV = Stroke volume O2 = Oxygen delivery Myocardium = Heart muscle</p> Signup and view all the answers

During which type of exercise does the cardiovascular system demonstrate the greatest changes?

<p>Maximal exercises (D)</p> Signup and view all the answers

Blood flow distribution during exercise is consistent regardless of exercise intensity.

<p>False (B)</p> Signup and view all the answers

What is the effect of increased venous return during exercise?

<p>It leads to an increase in stroke volume (SV).</p> Signup and view all the answers

What percentage of carbon dioxide is transported via the bicarbonate system?

<p>70-75% (A)</p> Signup and view all the answers

Carbonic anhydrase is an enzyme that facilitates the reaction between carbon dioxide and water.

<p>True (A)</p> Signup and view all the answers

What is formed when carbon dioxide binds to hemoglobin in low oxygen conditions?

<p>carbaminohemoglobin</p> Signup and view all the answers

The condition where an increase in H+ ions leads to a decrease in blood pH is referred to as __________.

<p>acidosis</p> Signup and view all the answers

Match the following components involved in carbon dioxide transport to their respective functions:

<p>Bicarbonate ions = Help regulate blood pH Carbaminohemoglobin = Transport CO2 bound to hemoglobin Carbonic acid = Intermediate in CO2 transport Carbonic anhydrase = Catalyzes reaction of CO2 and water</p> Signup and view all the answers

Which activity increases ventilation and affects blood pH?

<p>Increased exercise intensity (D)</p> Signup and view all the answers

How does increased ventilation affect H+ ion concentration in the blood?

<p>It lowers the concentration of H+ ions.</p> Signup and view all the answers

Blood pH is generally maintained very close to a pH of 6.4.

<p>False (B)</p> Signup and view all the answers

What is the term for the difference in concentration of a substance between two areas?

<p>Concentration gradient (A)</p> Signup and view all the answers

The partial pressure of a gas remains constant regardless of changes in barometric pressure.

<p>False (B)</p> Signup and view all the answers

What is the relationship between the concentration gradient and the rate of diffusion?

<p>As the concentration gradient increases, the rate of diffusion also increases.</p> Signup and view all the answers

Henry's law states that the amount of gas that dissolves into a liquid is proportional to the partial pressure and the ______ of the gas.

<p>solubility</p> Signup and view all the answers

Match the following factors affecting diffusion rates with their descriptions:

<p>Concentration gradient = The difference in concentration of a substance between two areas Thickness of the barrier = The distance a substance must travel to move between two areas Solubility of the gas = The ability of a gas to dissolve in a liquid Partial pressure of the gas = The pressure exerted by a gas within a mixture</p> Signup and view all the answers

What part of the brain is primarily responsible for controlling ventilation?

<p>Brain Stem (D)</p> Signup and view all the answers

The inspiratory centre generates a continuous signal to the respiratory muscles.

<p>False (B)</p> Signup and view all the answers

Name the two specialized respiratory centers located in the pons.

<p>Pneumotaxic and apneustic centres</p> Signup and view all the answers

The ________ and the ________ are the two main parts of the brain stem involved in the regulation of ventilation.

<p>medulla oblongata, pons</p> Signup and view all the answers

Match the following brain areas with their functions in ventilation:

<p>Medulla Oblongata = Contains the inspiratory and expiratory centres Pons = Ensures smooth transition between inhalation and exhalation Cerebrum = Involved in voluntary control of breathing Cerebellum = Coordinates muscle movements related to breathing</p> Signup and view all the answers

Which of the following is NOT a function of sensory systems in respiration?

<p>Regulate blood pressure during inhalation (D)</p> Signup and view all the answers

The control of breathing is a process under conscious control.

<p>False (B)</p> Signup and view all the answers

What is the primary factor that influences muscle contraction related to breathing?

<p>Stimulation from the central nervous system</p> Signup and view all the answers

Which factor does NOT contribute to the increased unloading of oxygen during exercise?

<p>Increase in PO2 gradient (D)</p> Signup and view all the answers

The Bohr shift results in a rightward shift of the oxyhemoglobin dissociation curve.

<p>False (B)</p> Signup and view all the answers

What is the term used to describe the difference in oxygen content between arterial blood and venous blood?

<p>a-vO2 difference</p> Signup and view all the answers

During exercise, the __________ of the skeletal muscle increases, resulting in a higher demand for oxygen.

<p>cellular respiration</p> Signup and view all the answers

Match the following changes during exercise to their effects on oxygen unloading:

<p>Increased PCO2 = Promotes oxygen unloading Decreased pH = Enhances oxygen release Increased temperature = Supports faster dissociation of oxygen Increased muscle activity = Increases oxygen demand</p> Signup and view all the answers

What is the observed change in respiratory function due to regular aerobic training?

<p>Increased ventilatory efficiency (VE) during maximal exercise (A)</p> Signup and view all the answers

Regular aerobic training significantly enhances the strength of the respiratory muscles.

<p>True (A)</p> Signup and view all the answers

The difference between arterial and venous oxygen content reflects how much oxygen has been __________ to the muscle during exercise.

<p>delivered</p> Signup and view all the answers

What is considered a normal range for blood pressure in humans?

<p>90/60 mmHg to 120/80 mmHg (D)</p> Signup and view all the answers

Systolic blood pressure typically increases during aerobic exercise, while diastolic blood pressure remains unchanged.

<p>True (A)</p> Signup and view all the answers

What phenomenon occurs after exercise, causing blood pressure to drop below normal resting values?

<p>post-exercise hypotension</p> Signup and view all the answers

Blood pressure greater than __________ mmHg is considered hypertension.

<p>140/90</p> Signup and view all the answers

Match the following causes of hypertension with their descriptions:

<p>Obesity = Excess body weight contributing to increased blood pressure Smoking = Tobacco use leading to vascular damage Aging = Natural increase in blood pressure with age Kidney disease = Impaired kidney function influencing fluid balance</p> Signup and view all the answers

What lifestyle changes are recommended for individuals with elevated blood pressure?

<p>Reduce body weight and increase aerobic exercise (B)</p> Signup and view all the answers

Resistance exercise leads to long-term increases in both systolic and diastolic blood pressure during the activity.

<p>False (B)</p> Signup and view all the answers

Within how many weeks does aerobic exercise typically lead to improvements in resting blood pressure for people with moderate to high blood pressure?

<p>three weeks to three months</p> Signup and view all the answers

Which of the following conditions is characterized by airflow reduction and often requires supplemental oxygen therapy?

<p>Chronic obstructive pulmonary disease (COPD) (C)</p> Signup and view all the answers

Asthma symptoms can be quickly relieved through medication.

<p>True (A)</p> Signup and view all the answers

What is another term for shortness of breath commonly associated with respiratory diseases?

<p>dyspnea</p> Signup and view all the answers

The process of measuring the amount of air expired and the concentration of oxygen in that air to determine oxygen consumption is called __________.

<p>indirect calorimetry</p> Signup and view all the answers

Match the following respiratory conditions with their characteristics:

<p>Asthma = Characterized by bronchial spasms and excess mucus COPD = Chronic condition with persistent airflow limitation Dyspnea = Term for shortness of breath Exercise-induced asthma = Triggered by physical exertion</p> Signup and view all the answers

Which factor is NOT typically known to stimulate an asthma attack?

<p>Excess sleep (D)</p> Signup and view all the answers

Oxygen consumption (VO2) is independent of physical workload.

<p>False (B)</p> Signup and view all the answers

What is the term used to describe the total blood flow distributed throughout the body?

<p>cardiac output (Q)</p> Signup and view all the answers

What is the term for the point at which pulmonary ventilation increases rapidly in relation to workload?

<p>Ventilatory threshold (A)</p> Signup and view all the answers

Proper aerobic training can shift the onset of blood lactate accumulation (OBLA) curve to occur earlier.

<p>False (B)</p> Signup and view all the answers

What is the role of lactic acid during intensive exercise?

<p>Lactic acid accumulates as a by-product of anaerobic metabolism when the aerobic systems can no longer meet energy demands.</p> Signup and view all the answers

The exercise intensity where lactate accumulation begins to rise rapidly is referred to as the ________ threshold.

<p>lactate</p> Signup and view all the answers

Match the following thresholds with their corresponding characteristics:

<p>Ventilatory Threshold = Occurs with significant lactic acid accumulation Lactate Threshold = Associated with the onset of anaerobic metabolism Onset of Blood Lactate Accumulation (OBLA) = Represents the point of rapid lactate increase</p> Signup and view all the answers

How does aerobic training primarily increase aerobic capacity?

<p>By enhancing the efficiency of the aerobic metabolic systems (A)</p> Signup and view all the answers

Blood lactate concentrations initially remain high during the onset of exercise.

<p>False (B)</p> Signup and view all the answers

At what percentage of VO2max does ventilatory threshold typically occur?

<p>65-85%</p> Signup and view all the answers

Flashcards

Coronary Artery Disease

A buildup of fatty deposits within the walls of coronary arteries, which can restrict blood flow to the heart.

What causes a heart attack?

A rupture of the fatty plaque in the coronary artery, leading to blood clot formation that obstructs blood flow to the heart.

Heart Attack (Myocardial Infarction)

A condition where blood flow to a part of the heart muscle is blocked, resulting in damage due to oxygen deprivation.

Cardiac Output (Q)

The amount of blood pumped by the left ventricle of the heart in one minute.

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Stroke Volume

The volume of blood pumped out by the heart with each beat.

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Heart Rate

The number of times the heart beats per minute.

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Cardiovascular Dynamics

The study of how the cardiovascular system functions and adapts to different demands.

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Adaptation in Cardiovascular Dynamics

The process of the cardiovascular system adapting to changing needs of the body, like during exercise.

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What is the most potent stimulator of blood flow in skeletal muscle?

Nitric oxide, a compound produced during muscle contraction, is a powerful stimulator of blood flow. Its role in controlling blood flow is significant, making it a subject of extensive research.

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What are arterioles and their function?

Arterioles are the small branches of arteries that connect to capillaries, where gas exchange happens. These vessels are surrounded by smooth muscle, which allows for regulation of blood flow.

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What are capillaries and what makes them unique?

These tiny vessels are the smallest blood vessels in the body, responsible for the exchange of gases and nutrients between blood and tissues. They are so small that red blood cells barely fit, and their thin walls (one cell thick) allow for efficient exchange.

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How are gases and nutrients transferred between blood and tissues?

The transfer of gases and nutrients from the blood to the tissues is primarily done through a process called diffusion. Substances move from areas of higher concentration to areas of lower concentration.

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What is the function of arteries?

Arteries are blood vessels that carry oxygen-rich blood away from the heart to the body's tissues. The only exception is the pulmonary artery, which carries deoxygenated blood to the lungs.

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What is the function of veins?

Veins are blood vessels responsible for carrying deoxygenated blood back to the heart. The exception is the pulmonary vein, which carries oxygenated blood from the lungs to the heart.

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What is the pulmonary circulation?

The pulmonary circulation involves the flow of blood from the heart to the lungs and back. This circulation is responsible for oxygenating the blood.

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What is the systemic circulation?

The systemic circulation involves the flow of blood from the heart to the rest of the body and back. This circulation is responsible for delivering oxygen and nutrients to the body's tissues.

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Blood Flow Redistribution During Exercise

During exercise, the cardiovascular system prioritizes oxygen delivery to working muscles by increasing blood flow and redirecting it from less active organs.

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Stroke Volume (SV)

The amount of blood ejected by the heart with each beat.

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Cardiovascular System Improvement with Exercise

The ability of the heart to pump blood more efficiently, both at rest and during exercise.

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Heart Hypertrophy

The increased size of the heart muscle due to regular exercise, leading to increased stroke volume and cardiac output.

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Increased Capillary Density in Heart

The increased number of tiny blood vessels in the heart muscle, improving oxygen supply to the heart itself.

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Unaltered Brain Blood Flow During Exercise

The brain receives a constant supply of blood, even during exercise, ensuring its proper function.

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Cardiovascular Adaptation to Exercise

The process by which the heart adapts to physical activity, leading to increased efficiency and improved health.

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Ventilation

The process of moving air in and out of the lungs.

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Minute Ventilation (VE)

The volume of air moved by the lungs in one minute.

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Tidal Volume (VT)

The amount of air inhaled or exhaled in a single breath.

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Respiratory Frequency (f)

The number of breaths taken per minute.

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Diaphragm

The muscle that separates the chest cavity from the abdominal cavity. It contracts to expand the chest cavity during inhalation.

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Intercostal Muscles

Muscles between the ribs that help expand the chest cavity during inhalation.

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Inspiration

The active process of breathing in, requiring muscle contraction.

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Expiration

The passive or active process of breathing out.

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Bicarbonate System

The process where CO2 diffuses into red blood cells and reacts with water, forming carbonic acid, which then dissociates into bicarbonate ions and hydrogen ions. This is the main way CO2 is transported in the blood.

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Carbonic Anhydrase

An enzyme present in red blood cells that speeds up the reaction between CO2 and water, forming carbonic acid. This plays a critical role in CO2 transport.

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Carbaminohemoglobin Formation

The binding of CO2 to hemoglobin, forming a compound called carbaminohemoglobin. This is a minor way CO2 is transported in the blood, especially when oxygen levels are low.

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Partial Pressure of CO2 (PCO2)

The pressure exerted by a specific gas in a mixture of gases, like the partial pressure of CO2 in the blood.

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CO2 Release in the Lungs

The process by which CO2 is released from the blood into the alveoli in the lungs and exhaled, mainly driven by the higher partial pressure of oxygen in the lungs.

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CO2 Diffusion

The movement of CO2 across cell membranes, like from the tissues to the blood or from the blood to the lungs, driven by concentration differences.

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Blood pH

The balance between acidity and alkalinity in the blood, measured on a pH scale. A lower pH indicates acidity, while a higher pH indicates alkalinity.

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What is asthma and what causes it?

Asthma, a disease where the airways narrow and become inflamed, resulting in shortness of breath and wheezing. This occurs due to the contraction of smooth muscles in the airways, excess mucus production, and swelling of the airway lining.

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What is Chronic Obstructive Pulmonary Disease (COPD)?

Chronic obstructive pulmonary disease (COPD) is a group of lung diseases that cause airflow obstruction and difficulty breathing. Unlike asthma, these conditions are persistent and can't be easily relieved with medication.

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What is oxygen consumption (VO2) and how is it measured?

Oxygen consumption (VO2) measures the amount of oxygen used by the body during metabolic processes; it's the difference between inhaled and exhaled oxygen.

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How does workload affect oxygen consumption?

VO2 is directly proportional to workload; higher workload demands more oxygen.

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What is indirect calorimetry?

Indirect calorimetry is a method to measure VO2 using a metabolic cart which measures the amount of air expired and the oxygen content within it.

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What is VO2max?

VO2max is the maximum amount of oxygen your body can use during intense exercise. This is a key indicator of your fitness level.

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What is cardiac output (Q)?

Cardiac output (Q) is the total amount of blood pumped out by the heart per minute, representing the overall blood flow throughout the body.

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What factors influence VO2 (oxygen consumption)?

VO2 is influenced by both the delivery of oxygen to the muscles and tissues, and the ability of those tissues to uptake oxygen.

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What is systolic blood pressure?

Systolic blood pressure represents the pressure in the arteries when the heart contracts and pumps blood out.

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What is diastolic blood pressure?

Diastolic blood pressure reflects the pressure in the arteries when the heart is relaxed and refilling with blood.

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How does endurance exercise affect blood pressure?

During endurance exercise, systolic blood pressure increases proportionally to the exercise intensity. This means the harder you work, the higher your systolic pressure goes.

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How does resistance exercise affect blood pressure?

Resistance exercise, like weightlifting, causes short but significant spikes in both systolic and diastolic blood pressure. The intensity of the exercise dictates the degree of pressure increase.

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What is post-exercise hypotension?

Post-exercise hypotension is the temporary drop in blood pressure below resting levels that occurs after physical activity, even with low-intensity exercise.

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What is hypertension?

Hypertension, also known as high blood pressure, is persistently elevated blood pressure exceeding 140/90 mmHg. It's a major risk factor for cardiovascular disease.

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How can exercise help lower blood pressure?

Aerobic exercise, combined with dietary modifications, can effectively reduce high blood pressure. Within three weeks to three months, noticeable improvements can be seen.

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What dietary changes can help lower blood pressure?

A diet low in saturated fats and cholesterol, and high in fiber and complex carbohydrates, is recommended for individuals with elevated blood pressure.

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Respiratory Control Centers

Specialized nerve centers in the brainstem that regulate the rate and depth of breathing. They control the contraction and relaxation of respiratory muscles.

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Inspiratory Rhythm

The rhythmic signal generated by inspiratory neurons in the medulla oblongata that stimulates respiratory muscles.

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Pneumotaxic and Apneustic Centers

A pair of respiratory centers in the pons that regulate the transition between inhalation and exhalation, making breathing smooth.

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Oxygen and CO2 Exchange

The primary factor that triggers breathing is the need for oxygen (O2) and the removal of carbon dioxide (CO2) from the body.

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Sensory Feedback Systems

The sensory systems that monitor blood oxygen and CO2 levels, pH, and stretch receptors in the lungs. This feedback helps regulate breathing to maintain optimal gas exchange.

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Diffusion

The process by which a substance moves from an area of high concentration to an area of low concentration.

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Concentration Gradient

The difference in concentration of a substance between two regions, driving the movement of that substance from an area of higher concentration to an area of lower concentration.

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Partial Pressure

The pressure exerted by a specific gas in a mixture of gases. It's determined by the fraction of that gas in the mixture and the total pressure.

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Henry's Law

The rate of diffusion of a gas across a membrane is directly proportional to the pressure difference of the gas across the membrane and the solubility of the gas in the membrane.

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Diffusion Gradient

The difference in partial pressure of a gas between two regions. The greater the difference, the faster the diffusion of the gas.

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Barrier Thickness

The thickness of the barrier between two regions influences the rate of diffusion. The thicker the barrier, the slower the diffusion.

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Ventilatory Threshold

The point during exercise where ventilation increases rapidly, usually occurring around 65-85% of VO2max.

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Lactic Acid

A by-product of anaerobic metabolism that accumulates in the blood during intense exercise.

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Lactate Threshold

The point during exercise where blood lactate levels start to rise exponentially.

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Onset of Blood Lactate Accumulation (OBLA)

The exercise intensity at which blood lactate starts to accumulate rapidly.

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Anaerobic Threshold

Increased reliance on anaerobic metabolism during exercise, leading to fatigue and burning sensations.

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Aerobic Capacity

The ability of the body to use oxygen during exercise. It's a measure of aerobic fitness.

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VO2max

The maximum amount of oxygen your body can use during intense exercise. A key indicator of fitness.

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Aerobic Training

The process of training to improve aerobic capacity, leading to increased VO2max and better endurance.

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What is a-vO2 difference?

The difference in oxygen content between arterial blood entering a muscle and venous blood leaving the same muscle, reflecting the amount of oxygen delivered to the muscle during activity.

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What is the Bohr Shift?

The process of shifting the oxyhemoglobin dissociation curve to the right, allowing for greater oxygen unloading at tissues, especially during exercise.

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How does exercise affect oxygen unloading?

Increased CO2 production, decreased pH (acidity), and increased temperature - all factors that promote oxygen release from hemoglobin during exercise.

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How does training affect the respiratory system?

The increased strength and endurance of respiratory muscles resulting from regular aerobic training.

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Is the respiratory system a limiting factor for exercise?

Despite being crucial for oxygen delivery, the respiratory system is typically NOT the limiting factor for exercise performance in healthy individuals.

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How does training affect minute ventilation?

An increase in minute ventilation (VE) during exercise, indicating more air being moved in and out of the lungs.

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What is ventilation?

The process of moving air in and out of the lungs, involves both inspiration (inhaling) and expiration (exhaling).

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Study Notes

Cardiovascular System

  • Electrical Signal Transmission: The electrical signal starts at the sinoatrial node (SA node), travels to the atrioventricular node (AV node), then through the bundle of His, bundle branches, and Purkinje fibers, initiating heart contractions. Specialized tissues ensure coordinated contraction of atria & ventricles.
  • SA Node Function: The SA node acts as the heart's natural pacemaker, setting basic contraction rate (~70-80 bpm) independently of the nervous system.
  • AV Node Function: The AV node takes over pacing if the SA node fails, but normally transmits the signal to the ventricles, delaying ventricular contraction to allow atrial emptying.
  • Bundle of His/Branches/Purkinje Fibers: The electrical signal is passed through these specialized tissues to the ventricles, coordinating their contraction, ensuring a synchronized contraction of the ventricles.
  • Heart Contraction Sequence: Atrial contraction precedes ventricular contraction, pushing blood into the ventricles, then into the aorta and pulmonary arteries. This sequence is crucial for efficient blood pumping.

Vascular System

  • Arteries: Thick-walled, muscular vessels that carry oxygenated blood away from the heart (except pulmonary arteries). They are elastic to accommodate blood pressure changes during the cardiac cycle; withstanding high pressure.
  • Arterioles: Smaller branches of arteries, with muscle to regulate blood flow to specific tissues (influenced by nervous system and local factors). This regulation ensures blood supply matches tissue needs.
  • Capillaries: Microscopic vessels with thin walls (one cell thick) for gas exchange between blood and tissues. Millions present throughout the body; optimum surface area for diffusion.
  • Venules: Small veins that collect blood from capillaries.
  • Veins: Wider vessels with thinner walls and valves to prevent backflow as blood returns to the heart. Larger veins such as superior and inferior vena cava; lower pressure.
  • Blood Flow Through Vessels: Blood flows from arteries to arterioles to capillaries, venules and veins, becoming progressively wider and returning to the heart; controlled by pressure gradients & valves.

Capillaries

  • Gas Exchange: Capillaries facilitate the exchange of oxygen, carbon dioxide, nutrients, and waste products between the blood and tissues. Exchange occurs via diffusion.
  • Diffusion: Gases and nutrients move from areas of higher concentration in the blood to lower concentration in the tissues. The same principle applies in reverse.

Blood Flow Return

  • Thoracic Pump: Changes in pressure within the chest cavity during breathing help move blood back to the heart. Changes in pressure facilitate venous return.
  • Skeletal Muscle Pump: Muscle contractions during exercise exert pressure on veins, pushing blood towards the heart. This mechanism aids venous return during activity.
  • Valves: One-way valves within veins prevent backflow of blood, ensuring unidirectional movement. Prevent backflow, facilitating unidirectional movement.

Blood Pressure

  • Systolic Pressure: Maximum pressure in the arteries during ventricular contraction.
  • Diastolic Pressure: Minimum pressure during ventricular relaxation.
  • Measurement: Blood pressure is typically measured in mmHg (millimeters of mercury), recorded as systolic/diastolic.
  • Importance: Blood pressure is a crucial measurement in circulatory function, and a marker for cardiovascular health; indicative of workload.

Blood Composition

  • Plasma: Fluid portion of blood, carrying nutrients, hormones, and waste products.
  • Blood Cells: Erythrocytes (red blood cells), transport oxygen. Leukocytes (white blood cells), part of the immune system. Platelets, involved in blood clotting.

Cardiovascular Disease

  • Atherosclerosis: Hard deposits of cholesterol (plaque) accumulate on artery walls, narrowing the arteries.
  • Risk Factors: Poor diet, smoking, elevated blood lipids, hypertension, family history, physical inactivity increase risk.
  • Heart Attack: A major consequence of atherosclerosis, where blood flow to the heart muscle is blocked. Leading to myocardial infarction (heart attack).
  • Hypertension: Persistent high blood pressure. Requires medical intervention if uncontrolled.

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Description

This quiz covers the essential functions and pathways of the cardiovascular system, including the electrical signal transmission that initiates heart contractions. Key components like the SA node, AV node, and the structure of arteries are highlighted to enhance your understanding of heart function.

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