Test 2 Practice Questions Flashcards
What is the process by which the vascular system maintains homeostasis through local and systemic mechanisms, including the baroreceptor reflex?
a) Capillary filtration
b) Vasoconstriction and vasodilation
c) Blood clotting
d) Endothelial cell activation
b) Vasoconstriction and vasodilation
Which of the following is the correct sequence for the stages of fetal heart development?
a) Formation of the four-chambered heart > atrial and ventricular septation > closure of fetal shunts
b) Formation of the heart tube > folding and looping > atrial and ventricular septation
c) Formation of the heart tube > atrial septation > formation of coronary circulation
d) Looping of the heart tube > formation of the septal valves > closure of the ductus arteriosus
b) Formation of the heart tube > folding and looping > atrial and ventricular septation
During exercise, oxygen delivery to tissues increases due to:
a) An increase in hemoglobin’s affinity for oxygen
b) Increased ventilation and an increase in cardiac output
c) Decreased production of carbon dioxide in the muscles
d) Decreased pH levels in the blood
b) Increased ventilation and an increase in cardiac output
Carbon dioxide is primarily transported in the blood in which form?
a) Dissolved in plasma
b) Bound to hemoglobin
c) As bicarbonate ions HCO3-
d) Bound to albumin
c) As bicarbonate ions (HCO3-)
In the lungs, oxygen diffuses from the alveoli into the blood because:
a) The partial pressure of oxygen in the blood is higher than in the alveoli
b) The partial pressure of carbon dioxide in the alveoli is higher than in the blood
c) The partial pressure of oxygen in the alveoli is higher than in the blood
d) The concentration of nitrogen is higher in the alveoli
c) The partial pressure of oxygen in the alveoli is higher than in the blood
The oxyhemoglobin dissociation curve demonstrates that hemoglobin’s affinity for oxygen:
a) Increases as the partial pressure of carbon dioxide rises
b) Decreases as the pH of the blood becomes more alkaline
c) Increases with higher temperatures
d) Decreases as the partial pressure of oxygen increases
The myocardium of the heart is primarily composed of:
a) Epithelial tissued
b) Cardiac muscle tissue
c) Smooth muscle tissue
d) Connective muscle tissue
b) Cardiac muscle tissue
What ion is most important in creating the membrane potential of cardiac contractile cells during depolarization?
a) Sodium (Na+)
b) Potassium (K+)
c) Calcium (Ca+2)
d) Chloride (Cl-)
a) Sodium (Na+)
Which of the following is the correct order of airflow from the trachea to the alveoli?
a) Trachea > Bronchi > Bronchioles > Alveolar ducts > Alveoli
b) Trachea > Bronchi > Alveoli
c) Trachea > Alveoli > Bronchioles > Bronchi
d) Trachea > Bronchioles > Alveoli > Alveolar sacs
a) Trachea > Bronchi > Bronchioles > Alveolar ducts > Alveol
A low partial pressure of oxygen (PaO2) in the blood, along with increased carbon dioxide (PaCO2), typically results in:
a) Increased hemoglobin affinity for oxygen
b) Decreased oxygen delivery to tissues
c) Increased hemoglobin oxygen binding
d) Decreased carbon dioxide release from tissues
b) Decreased oxygen delivery to tissues
Which of the following is the outermost membrane surrounding the heart?
a) Epicardium
b) Myocardium
c) Endocardium
d) Pericardium
d) Pericardium
The primary function of the alveoli in the lungs is to:
a) Filter dust and bacteria from incoming air
b) Warm and humidify the air entering the lungs
c) Allow gas exchange (oxygen and carbon dioxide) between the blood and air
d) Produce mucus to trap foreign particles
c) Allow gas exchange (oxygen and carbon dioxide) between the blood and air
The pressure that forces fluid and dissolved substances out of the capillaries into the surrounding tissues is called:
a) Osmotic pressure
b) Capillary hydrostatic pressure
c) Blood pressure
d) Oncotic pressure
b) Capillary hydrostatic pressure
The role of surfactant in the lungs is to:
a) Protect the lungs from allergens and bacteria
b) Facilitate the exchange of gases between alveoli and capillaries
c) Reduce surface tension in the alveoli, preventing lung collapse and aiding in lung expansion
d) Warm and humidify the air entering the lungs
c) Reduce surface tension in the alveoli, preventing lung collapse and aiding in lung expansion
Airway dilation is primarily controlled by:
a) The parasympathetic nervous system and acetylcholine release
b) Smooth muscle relaxation and sympathetic nervous system activation
c) The vagus nerve and histamine release
d) The release of adrenaline and vasoconstriction
b) Smooth muscle relaxation and sympathetic nervous system activation
What is an accurate description of the primary function of veins in the circulatory system?
a) Carry oxygenated blood from the heart to the tissues
b) Exchange gases and nutrients at the tissue level
c) Return deoxygenated blood to the heart, aided by valves and skeletal muscles contraction
d) Control blood flow in response to body temperature changes
c) Return deoxygenated blood to the heart, aided by valves and skeletal muscles contraction
Which of the following best describes the key event during the isovolumetric contraction phase of the cardiac cycle?
a) Blood enters the ventricles from the atria
b) The semilunar valves open and blood is ejected from the ventricles
c) The ventricles contract, but all valves are closed, causing pressure to rise
d) The atria contract, pushing blood into the ventricles
c) The ventricles contract, but all valves are closed, causing pressure to rise
Which of the following is most likely to affect arterial blood flow?
a) Blood viscosity
b) Venous return
c) Lymphatic drainage
d) Heart rate
a) Blood viscosity
The “dub” or S2 sound heard during the cardiac cycle is caused by:
a) The closing of the semilunar (pulmonic/aortic) valves
b) The closing of the atrioventricular (AV) valves
c) The opening of the semilunar valves
d) The atrial contraction
The closing of the semilunar (pulmonic/aortic) valves
Which of the following best describes how the diameter of blood vessels affects blood flow?
a) As the diameter of the blood vessel increases, blood flow decreases
b) As the diameter of the blood vessel increases, blood flow increases
c) Blood flow is independent of the blood vessel diameter
d) A decrease in vessel diameter has no effect on blood flow
b) As the diameter of the blood vessel increases, blood flow increases
Which of the following accurately describes the role of the sinoatrial (SA) node in the establishment of normal sinus rhythm?
a) The SA node generates electrical impulses that trigger atrial contraction and set the rhythm of the heart
b) The SA node slows down electrical impulses, regulating heart rate during rest
c) The SA node receives signals from the vagus nerve to slow heart rate
d) The SA node only controls the rate of ventricular contraction
a) The SA node generates electrical impulses that trigger atrial contraction and set the rhythm of the heart
The pleurae of the lungs are responsible for:
a) Protecting the lungs from infection
b) Regulating airflow in and out of the lungs
c) Facilitating smooth lung expansion and contraction by reducing friction between the lungs and chest wall
d) Filtering blood before it reaches the lungs
c) Facilitating smooth lung expansion and contraction by reducing friction between the lungs and chest wall
At high altitudes, oxygenation is affected by:
a) A decrease in the partial pressure of oxygen in the atmosphere
b) An increase in the partial pressure of oxygen in the lungs
c) A decrease in the amount of hemoglobin in the blood
d) An increase in atmospheric pressure
a) A decrease in the partial pressure of oxygen in the atmosphere
Which of the following best describes the primary function of arteries?
a) To exchange gases, nutrients and waste products with tissues
b) To carry oxygenated blood away from the heart to the organs and tissues
c) To return deoxygenated blood from the organs to the heart
d) To regulate blood flow based on the body’s immediate needs
b) To carry oxygenated blood away from the heart to the organs and tissues
The process of airway clearance involves which of the following steps?
a) The movement of air through the bronchi to facilitate gas exchange
b) The secretion of mucus to trap particles and pathogens
c) The activation of the diaphragm to force out trapped particles
d) The movement of cilia in the respiratory tract to move mucus and trapped particles toward the throat
d) The movement of cilia in the respiratory tract to move mucus and trapped particles toward the throat
The hepatic portal system functions to:
a) Circulate oxygenated blood from the lungs to the heart
b) Direct blood flow from the gastrointestinal tract to the liver for detoxification and nutrient processing
c) Return deoxygenated blood to the heart from the lower body
d) Transport oxygenated blood from the placenta to the fetal heart
b) Direct blood flow from the gastrointestinal tract to the liver for detoxification and nutrient processing
Which of the following terms refers to the amount of oxygen bound to hemoglobin in the blood?
a) Hypoxemia
b) Oxygen saturation (SaO2)
c) Oxygen content (CaO2)
d) Partial pressure of oxygen (PaO2)
b) Oxygen saturation (SaO2)
In fetal circulation, the ductus arteriosus serves to:
a) Direct blood flow from the right atrium to the left atrium
b) Allow oxygenated blood from the placenta to enter the heart directly
c) Bypass the lungs by connecting the pulmonary artery to the aorta
d) Deliver blood from the left ventricle to the brain
c) Bypass the lungs by connecting the pulmonary artery to the aorta
The relationship between ventilation, perfusion, and partial gas pressures is critical for:
a) Ensuring blood flow is diverted from the lungs during exercise
b) Maximizing the efficiency of gas exchange between the lungs and blood
c) Preventing the collapse of the alveoli
d) Increasing the volume of air entering the lungs during inspiration
b) Maximizing the efficiency of gas exchange between the lungs and blood
Airway constriction, which narrows the air passages, is often caused by:
a) Smooth muscle relaxation in the bronchioles
b) The release of epinephrine and beta-agonist activity
c) Inflammation, increased mucus production, or the parasympathetic nervous system response
d) Increased lung compliance and surfactant production
c) Inflammation, increased mucus production, or the parasympathetic nervous system response
The process of fetal respiratory development includes:
a) The development of functional alveoli, capable of gas exchange, only after birth
b) Formation of alveoli and airways starting at 20 weeks, but lacking surfactant production until birth
c) Lungs are fully developed with surfactant production by 24 weeks gestation
d) The fetus uses its lungs for oxygen exchange early in pregnancy, but relies on the placenta later on
b) Formation of alveoli and airways starting at 20 weeks, but lacking surfactant production until birth
The movement of which ion primarily contributes to the plateau phase (Phase 2) of the action potential in cardiac muscle cells?
a) Potassium (K+)
b) Sodium (Na+)
c) Calcium (Ca+2)
d) Chloride (Cl-)
c) Calcium (Ca+2)
The cardiovascular centers in the brainstem regulate heart rate by controlling:
a) The force of ventricular contraction only
b) The release of hormones that directly impact the heart’s rhythm
c) The activity of the autonomic nervous system, specifically the sympathetic and parasympathetic branches
d) The flow of blood through the coronary arteries
c) The activity of the autonomic nervous system, specifically the sympathetic and parasympathetic branches
What happens to oxygen saturation of hemoglobin as the partial pressure of oxygen (PO2) decreases?
a) Oxygen saturation increases significantly
b) Oxygen saturation decreases, as oxygen is released to the tissues
c) Oxygen saturation remains unchanged
d) Oxygen saturation increases slightly
b) Oxygen saturation decreases, as oxygen is released to the tissues
Which of the following blood vessels has the thickest muscular layer to accommodate the high pressure from the heart’s pumping action?
a) Veins
b) Arteries
c) Capillaries
d) Venules
b) Arteries
The process of inhalation involves which of the following?
a) The diaphragm relaxes and moves upward, forcing air out of the lungs
b) The diaphragm contracts and moves downward, expanding the lungs and allowing air to enter
c) The pleural muscles contract, raising the rib cage and forcing air into the lungs
d) The pleurae contract to push air into the lungs
b) The diaphragm contracts and moves downward, expanding the lungs and allowing air to enter
Which of the following structures serves as the primary passageway for air entering the lungs?
a) Trachea
b) Larynx
c) Pharynx
d) Bronchi
a) Trachea
Which blood vessels serve the lower limbs by supplying oxygenated blood?
a) Pulmonary veins
b) Carotid arteries
c) Subclavian arteries
d) Femoral arteries
d) Femoral arteries
What is the primary role of arterioles in the vascular system?
a) To carry oxygenated blood from the heart to the tissues
b) To control the distribution of blood to various tissues by constricting and dilating
c) To exchange nutrients and gases between blood and tissues
d) To return deoxygenated blood to the heart
b) To control the distribution of blood to various tissues by constricting and dilating
Which of the following blood vessels supplies oxygenated blood to the lungs?
a) Pulmonary artery
b) Pulmonary vein
c) Aorta
d) Superior vena cava
b) Pulmonary vein