Respiratory Regulation: Master the Control of Breathing

Question 1

In the brainstem respiratory center, which neurotransmitter is primarily responsible for stimulating the inspiratory muscles?

Accepted Answer

Acetylcholine

Answer

Dopamine

Answer

Epinephrine

Answer

Serotonin

Question 2

Which chemoreceptors are primarily responsible for detecting changes in arterial oxygen partial pressure?

Accepted Answer

Carotid bodies

Answer

Central chemoreceptors

Answer

Aortic bodies

Answer

Pulmonary chemoreceptors

Question 3

The Hering-Breuer reflex is an example of a:

Accepted Answer

Mechanoreflex

Answer

Baroreflex

Answer

Chemoreflex

Answer

Nociceptive reflex

Question 4

Which respiratory disorder is characterized by chronic airway inflammation and reversible airflow obstruction?

Accepted Answer

Asthma

Answer

Emphysema

Answer

Cystic fibrosis

Answer

Tuberculosis

Question 5

The primary role of surfactant in the lungs is to:

Accepted Answer

Reduce surface tension and prevent alveolar collapse

Answer

Increase airway resistance and promote mucus production

Answer

Enhance ciliary clearance and facilitate gas exchange

Answer

Stimulate immune responses and protect against infection

Question 6

Which of the following results from hyperventilation, a condition characterized by increased alveolar ventilation?

Accepted Answer

Elevated arterial pH

Answer

Reduced arterial pH

Answer

Elevated arterial PCO2

Answer

Reduced arterial PO2

Question 7

Which characteristic is associated with obstructive lung diseases?

Accepted Answer

Increased airway resistance

Answer

Decreased lung compliance

Answer

Increased vital capacity

Answer

Normal expiratory flow rates

Question 8

The Hering-Breuer reflex inhibits inspiration when:

Accepted Answer

Lung volume is excessive

Answer

Lung volume is insufficient

Answer

Airway pressure is elevated

Answer

Central carbon dioxide levels are low

Question 9

Which hormone stimulates increased respiratory rate?

Accepted Answer

Epinephrine

Answer

Progesterone

Answer

Thyroxine

Answer

Insulin

Question 10

The surfactant in the alveoli primarily serves to:

Accepted Answer

Reduce surface tension

Answer

Increase airway resistance

Answer

Promote alveolar collapse

Answer

Impede gas exchange

Question 11

The partial pressure gradient for oxygen exchange in the capillaries is primarily determined by:

Accepted Answer

Alveolar PO2 and capillary PO2

Answer

Capillary PO2 and arterial PO2

Answer

Arterial PO2 and alveolar PO2

Answer

Venous PO2 and capillary PO2

Question 12

Which of the following respiratory muscles is predominantly responsible for expiration?

Accepted Answer

Abdominal muscles

Answer

Diaphragm

Answer

External intercostals

Answer

Internal intercostals

Question 13

Which of the following is NOT a clinical application of lung ultrasound?

Accepted Answer

Monitoring ventilator settings

Answer

Diagnosing pneumonia

Answer

Guiding thoracentesis

Answer

Assessing diaphragm function

Question 14

Which chemoreceptor is NOT directly involved in monitoring arterial blood gases?

Accepted Answer

Baroreceptors

Answer

Carotid body

Answer

Aortic body

Answer

Medullary chemoreceptors

Question 15

Which neurotransmitter mediates the neural impulse from the respiratory center to the diaphragm, triggering contraction?

Accepted Answer

Acetylcholine

Answer

Epinephrine

Answer

GABA

Answer

Glutamate

Question 16

The Hering-Breuer reflex serves to:

Accepted Answer

Terminate inspiration at high lung volumes

Answer

Initiate expiration at low lung volumes

Answer

Adjust the breathing rate based on pH

Answer

Regulate airway resistance

Question 17

The optimal pH range for normal arterial blood is:

Accepted Answer

7.35-7.45

Answer

6.8-7.2

Answer

7.5-7.6

Answer

7.7-7.85

Question 18

Which of the following is a primary compensatory mechanism employed by the body to correct respiratory acidosis?

Accepted Answer

Renal bicarbonate reabsorption

Answer

Increased ventilation

Answer

Increased production of carbonic acid

Answer

Stimulation of erythropoiesis

Question 19

The innervation of the lungs is primarily provided by which division of the nervous system?

Accepted Answer

Autonomic nervous system

Answer

Somatic nervous system

Answer

Sympathetic nervous system exclusively

Answer

Parasympathetic nervous system exclusively

Question 20

What is the primary cause of breathing cessation during an obstructive sleep apnea episode?

Accepted Answer

Blockage of the upper airway

Answer

Decreased breathing effort

Answer

Low carbon dioxide levels in the lungs

Answer

Stiffness of the lungs

Question 21

Which of the following is the primary chemical stimulus for respiratory stimulation in healthy humans?

Accepted Answer

Increased arterial PaCO2

Answer

Decreased arterial pH

Answer

Increased arterial PaO2

Answer

Increased cerebral blood flow

Question 22

Where are the central chemoreceptors primarily located?

Accepted Answer

Medulla oblongata

Answer

Carotid bodies

Answer

Aortic bodies

Answer

Diaphragm

Question 23

Which of the following is NOT a primary function of the respiratory center in the medulla?

Accepted Answer

Regulation of airway caliber

Answer

Control of tidal volume

Answer

Control of respiratory rate

Answer

Modulation of heart rate

Question 24

What is the approximate normal respiratory rate for a healthy adult at rest?

Accepted Answer

12-16 breaths per minute

Answer

6-8 breaths per minute

Answer

18-22 breaths per minute

Answer

24-28 breaths per minute

Question 25

Which of the following lung volumes is measured during normal, quiet breathing?

Accepted Answer

Tidal volume

Answer

Inspiratory reserve volume

Answer

Expiratory reserve volume

Answer

Residual volume

Question 26

What is the primary function of surfactant in the lungs?

Accepted Answer

To decrease surface tension

Answer

To increase lung recoil

Answer

To facilitate gas exchange

Answer

To protect the airways from pathogens

Question 27

What is the primary mechanism of action of bronchodilators?

Accepted Answer

Relaxation of airway smooth muscle

Answer

Stimulation of mucus production

Answer

Inhibition of inflammatory mediators

Answer

Enhancement of ciliary function

Question 28

How does an increase in cardiac output impact pulmonary ventilation?

Accepted Answer

Pulmonary ventilation increases in proportion to the increase in cardiac output.

Answer

Pulmonary ventilation decreases to offset the increased cardiac output.

Answer

Pulmonary ventilation remains unchanged by changes in cardiac output.

Answer

Pulmonary ventilation decreases only if the increased cardiac output persists over time.

Question 29

Which of the following is the primary chemoreceptor that predominantly monitors arterial blood pH?

Accepted Answer

Central chemoreceptors located in the medulla oblongata

Answer

Peripheral chemoreceptors located in the carotid and aortic bodies

Answer

Muscle spindles located in skeletal muscles

Answer

Lung stretch receptors located in the airways

Question 30

The Hering-Breuer reflex, an inhibitory reflex triggered by lung inflation, involves the activation of:

Accepted Answer

Stretch receptors in the airways

Answer

Baroreceptors in the carotid sinus, which respond to changes in blood pressure

Answer

Chemoreceptors in the medulla oblongata, which respond to changes in blood pH and oxygen levels

Answer

Thermoreceptors in the skin, which respond to changes in body temperature

Question 31

Which of the following hormones, when released, stimulates the respiratory center in the brain, increasing the rate and depth of breathing?

Accepted Answer

Catecholamines, such as epinephrine and norepinephrine

Answer

Thyroid hormone, a hormone that regulates metabolism

Answer

Progesterone, a hormone involved in the menstrual cycle

Answer

Insulin, a hormone involved in glucose metabolism

Question 32

The concept of respiratory dead space refers to the:

Accepted Answer

Volume of gas that does not participate in gas exchange within the respiratory system

Answer

Volume of gas that is exhaled during a single breath

Answer

Volume of gas that is inspired during a single breath

Question 33

Which of the following conditions can result in respiratory alkalosis, a condition characterized by increased blood pH?

Accepted Answer

Hyperventilation, excessive and rapid breathing

Answer

Renal failure, a condition where kidneys malfunction

Answer

Hypoventilation, inadequate or shallow breathing

Answer

Metabolic acidosis, a condition of decreased blood pH due to excess acid production

Question 34

The respiratory quotient (RQ) is a dimensionless value used to estimate:

Accepted Answer

The type of substrate primarily being metabolized by the body

Answer

The efficiency of gas exchange in the lungs

Answer

The tidal volume, which is the volume of air moved in and out during a single breath

Answer

The respiratory rate, which is the number of breaths per minute

Question 35

Which of the following factors can cause a decrease in the partial pressure of oxygen (PaO2) in arterial blood?

Accepted Answer

Impairment of gas diffusion across the alveolar-capillary membrane

Answer

Increased hemoglobin concentration, which can increase oxygen-carrying capacity

Answer

Hyperventilation, excessive and rapid breathing

Question 36

The volume of air that remains in the lungs after a forced exhalation is referred to as:

Accepted Answer

Residual volume

Answer

Inspiratory reserve volume, the additional volume of air that can be inhaled beyond normal inhalation

Answer

Tidal volume, the volume of air moved in and out during a single breath

Answer

Vital capacity, the maximum volume of air that can be moved in and out of the lungs

Question 37

Which of the following statements about the regulation of ventilation is accurate?

Accepted Answer

Ventilation is primarily controlled by the levels of carbon dioxide and oxygen in the blood

Answer

Ventilation is solely dependent on the activity of the respiratory muscles, without any neural or chemical control

Answer

The respiratory center in the brain is not involved in the regulation of ventilation

Question 38

Which of the following conditions stimulates chemoreceptors to trigger an increase in respiratory rate and depth?

Accepted Answer

Increased PaCO2

Answer

Increased pH

Answer

Increased PaO2

Answer

Increased HCO3-

Question 39

Name the reflex responsible for preventing lung collapse during exhalation, ensuring adequate lung volume is maintained.

Accepted Answer

Hering-Breuer reflex

Answer

Baroreflex

Answer

Chemoreflex

Answer

Carotid sinus reflex

Question 40

Identify the characteristic feature of obstructive lung diseases, a group of conditions that hinder airflow.

Accepted Answer

Increased airway resistance

Answer

Decreased lung compliance

Answer

Reduced diffusion capacity

Answer

Increased alveolar surface area

Question 41

Determine the primary mechanism by which carbon dioxide is transported in the bloodstream.

Accepted Answer

Carbaminohemoglobin

Answer

Oxygen-hemoglobin dissociation curve

Answer

Plasma proteins

Answer

Lipid solubility

Question 42

Identify the muscle that is NOT involved in the process of respiration.

Accepted Answer

Gastrocnemius

Answer

Scalenes

Answer

External intercostals

Answer

Diaphragm

Question 43

Indicate the primary function of surfactant in the lungs, a substance that plays a crucial role in maintaining lung function.

Accepted Answer

Reduce surface tension

Answer

Clear mucus from the airways

Answer

Promote gas exchange

Answer

Increase lung compliance

Question 44

The primary neural center responsible for respiratory rhythm generation is the:

Accepted Answer

Medulla oblongata

Answer

Cerebellum

Answer

Hypothalamus

Answer

Pons

Question 45

During normal physiological conditions, which primary chemical factor stimulates ventilation?

Accepted Answer

Carbon dioxide

Answer

Bicarbonate

Answer

Nitrogen

Answer

Oxygen

Question 46

The primary function of the respiratory muscles is to:

Accepted Answer

Generate airflow in and out of the lungs

Answer

Filter inhaled air

Answer

Protect the airway from pathogens

Answer

Maintain body temperature

Question 47

Which mechanism contributes to the regulation of tidal volume?

Accepted Answer

Hering-Breuer reflex

Answer

Diving reflex

Answer

Baroreflex

Answer

Carotid body reflex

Question 48

The term for the difference in partial pressure of a gas between two compartments is:

Accepted Answer

Pressure gradient

Answer

Partial pressure

Answer

Concentration gradient

Answer

Gas exchange

Question 49

Which characteristic is unique to Type II alveolar cells?

Accepted Answer

Produce surfactant

Answer

Secrete mucus

Answer

Facilitate gas exchange

Question 50

In the bloodstream, oxygen is primarily transported by:

Accepted Answer

Hemoglobin binding

Answer

Bicarbonate buffering

Answer

Plasma solution

Answer

Red blood cell membranes

Question 51

Which respiratory disorder is characterized by airway inflammation and bronchospasm?

Accepted Answer

Asthma

Answer

Pneumonia

Answer

Pulmonary fibrosis

Answer

Emphysema

Question 52

The main purpose of mechanical ventilation is to:

Accepted Answer

Provide life support and improve oxygenation

Answer

Facilitate expectoration

Answer

Treat respiratory infections

Answer

Clear airway secretions