Respiratory System A&P Test 2

What are the main functions of the respiratory system?

The respiratory system brings oxygen into the body, expels carbon dioxide, produces vocal sounds, helps with the sense of smell, and regulates blood pH.

How does the respiratory system help regulate blood pH?

It controls carbon dioxide levels, which influence the acidity of the blood.

What is respiration, and what are its main processes?

Respiration is the process of exchanging gases between the atmosphere and body cells. It includes external respiration, internal respiration, and cellular respiration.

What is external respiration, and where does it occur?

External respiration is the exchange of gases between the lungs and the blood in the pulmonary capillaries.

What is internal respiration, and how does it differ from external respiration?

Internal respiration is the exchange of gases between the blood and body cells, whereas external respiration occurs between the lungs and blood.

What is cellular respiration, and why is oxygen essential for it?

Cellular respiration is the process of ATP production in the mitochondria, which requires oxygen to release energy and produces carbon dioxide as a byproduct.

What are the two major divisions of the respiratory system?

The respiratory system is divided into the upper and lower respiratory tracts.

What structures are included in the upper respiratory tract?

The upper respiratory tract consists of the nose, nasal cavity, sinuses, pharynx, and larynx.

What structures are included in the lower respiratory tract?

The lower respiratory tract includes the trachea, bronchial tree, and lungs.

What are the functions of the nostrils (external nares)?

Nostrils provide openings for air to enter and leave the nasal cavity and are protected by internal hairs that filter incoming particles.

What is the function of the nasal conchae?

The nasal conchae separate the nasal cavity into passageways, increasing surface area and helping warm, moisten, and filter incoming air.

How does the nasal cavity contribute to air filtration?

The mucous membrane traps dust and pathogens, while cilia move mucus toward the pharynx for swallowing.

What is the role of goblet cells in the nasal cavity?

Goblet cells produce mucus that traps dust, pathogens, and other particles in the air.

How does cilia help protect the respiratory system?

Cilia move mucus and trapped particles toward the pharynx, where they can be swallowed and destroyed by stomach acid.

What are the paranasal sinuses, and where are they located?

Paranasal sinuses are air-filled spaces in the maxillary, frontal, ethmoid, and sphenoid bones.

What are the functions of the sinuses?

They reduce skull weight, serve as resonant chambers for voice, and help warm and humidify incoming air.

What causes sinusitis, and what symptoms does it produce?

Sinusitis occurs when infections or allergies cause inflammation, blocking drainage and leading to sinus pressure and headaches.

What is the pharynx, and what are its functions?

The pharynx is a passageway for air and food and aids in sound production.

What are the three regions of the pharynx?

The three regions are the nasopharynx, oropharynx, and laryngopharynx.

What is the role of the nasopharynx in respiration?

The nasopharynx serves as an air passage and contains openings to the auditory tubes.

What is the role of the oropharynx in respiration and digestion?

The oropharynx serves as a passageway for both air and food.

How does the laryngopharynx connect to the larynx and esophagus?

The laryngopharynx is located inferior to the oropharynx and opens into the larynx and esophagus.

What are the main functions of the larynx?

The larynx moves air in and out of the trachea and houses the vocal cords.

What are the three main cartilages of the larynx?

The three large cartilages are the thyroid (Adam’s apple), cricoid, and epiglottic.

What is the difference between the false and true vocal cords?

False vocal cords do not produce sound and help close the airway, while true vocal cords produce sound when air is forced between them.

How is sound produced by the vocal cords?

Sound is created when air passes through the glottis, vibrating the true vocal cords.

What is the trachea, and where is it located?

The trachea is a cylindrical tube located anterior to the esophagus, leading from the larynx to the bronchi.

How does the trachea prevent collapse?

It contains 20 C-shaped rings of hyaline cartilage that keep it open.

What type of epithelium lines the trachea, and what is its function?

The trachea is lined with pseudostratified ciliated columnar epithelium, which moves mucus and trapped particles toward the pharynx.

What is a tracheostomy, and why is it performed?

A tracheostomy is a surgical procedure that creates an opening in the trachea to bypass an obstruction.

What is the bronchial tree, and how does it branch from the trachea?

The bronchial tree consists of branching airways from the trachea to the microscopic alveoli.

What are the primary bronchi, and where do they lead?

The primary bronchi are two large airways that branch from the trachea, each leading to a lung.

How many secondary (lobar) bronchi are in each lung?

The right lung has three secondary bronchi, and the left lung has two.

What are alveoli, and what is their role in gas exchange?

Alveoli are microscopic air sacs where oxygen and carbon dioxide are exchanged between the lungs and blood.

How does the structure of the respiratory tubes change as they get smaller?

Cartilage decreases, smooth muscle increases, and epithelium transitions from pseudostratified to simple squamous.

What are the lungs, and where are they located?

The lungs are spongy organs in the thoracic cavity, separated by the mediastinum.

How many lobes does each lung have?

The right lung has three lobes, and the left lung has two.

What is the hilum of the lung?

The hilum is the region where the bronchus, blood vessels, and nerves enter the lung.

What is the pleura, and what are its two layers?

The pleura is a double-layered membrane surrounding the lungs. The visceral pleura covers the lungs, and the parietal pleura lines the thoracic cavity.

What is the function of the pleural cavity?

It contains serous fluid that reduces friction during lung movement.

What is ventilation, and what are its two phases?

Ventilation is the movement of air into and out of the lungs, consisting of inspiration (inhalation) and expiration (exhalation).

How does atmospheric pressure play a role in breathing?

Air moves into the lungs when intra-alveolar pressure drops below atmospheric pressure.

What is Boyle’s Law, and how does it relate to breathing?

Boyle’s Law states that pressure and volume are inversely proportional. When lung volume increases, pressure decreases, drawing air in.

What muscles are involved in normal inspiration?

The diaphragm and external intercostal muscles.

What is surfactant, and why is it important for lung function?

Surfactant reduces surface tension in the alveoli, preventing their collapse.

How does forced inspiration differ from normal inspiration?

Forced inspiration uses additional muscles, such as the pectoralis minor and sternocleidomastoids, to expand the thoracic cavity more.

What is normal resting expiration, and why is it a passive process?

It occurs due to elastic recoil of lung tissues and does not require muscle contraction.

How does the loss of cilia impact the respiratory system?

It reduces the ability to remove mucus and trapped particles, increasing infection risk.

What muscles are involved in forced expiration?

Forced expiration involves the internal intercostal and abdominal muscles.

What is tidal volume (TV), and how much air does it involve?

Tidal volume is the amount of air moved in or out during a normal breath, typically about 500 mL.

What is inspiratory reserve volume (IRV), and when is it used?

IRV is the additional air that can be inhaled after a normal inspiration, usually around 3,000 mL.

What is expiratory reserve volume (ERV), and when is it used?

ERV is the extra air that can be exhaled after a normal expiration, typically about 1,100 mL.

What is residual volume (RV), and why is it important?

RV is the air that remains in the lungs after maximum expiration (about 1,200 mL), preventing lung collapse.

What is vital capacity (VC), and how is it calculated?

VC is the maximum amount of air that can be exhaled after a deep breath: VC = TV + IRV + ERV.

What is total lung capacity (TLC), and how is it calculated?

TLC is the total amount of air the lungs can hold: TLC = VC + RV, usually about 5,800 mL.

What are nonrespiratory air movements, and what causes them?

Nonrespiratory air movements include coughing, sneezing, laughing, and yawning, caused by reflexes or voluntary actions.

What is the function of coughing?

Coughing clears the lower respiratory tract by expelling irritants.

What is the function of sneezing?

Sneezing clears the upper respiratory passages by forcefully expelling air through the nasal cavity.

What is the physiological purpose of yawning?

The exact function is unclear, but yawning may help increase oxygen intake and alertness.

What causes hiccups?

Hiccups are caused by involuntary diaphragm spasms that trigger a sudden closure of the glottis.

How is speech produced in the respiratory system?

Speech is produced by air passing through the vocal cords, with modifications by the lips, tongue, and soft palate.

What part of the brain controls breathing?

The medulla oblongata and pons regulate breathing.

What is the function of the medullary respiratory center?

It controls the basic rhythm of breathing.

What is the role of the ventral respiratory group?

It sets the normal breathing rhythm.

What is the role of the dorsal respiratory group?

It modifies breathing rhythm in response to sensory input.

What do the pontine respiratory groups regulate?

They fine-tune breathing patterns by limiting the duration of inspiration.

What factors influence breathing rate and depth?

Factors include blood CO2 levels, O2 levels, pH, emotional state, and lung stretch receptors.

What is partial pressure, and how does it affect gas exchange?

Partial pressure is the pressure exerted by each gas in a mixture. Gases diffuse from high to low partial pressure.

What is the role of oxygen in respiration?

Oxygen is required for cellular respiration, which produces ATP.

How is oxygen transported in the blood?

98-99% of oxygen binds to hemoglobin in red blood cells, while 1-2% dissolves in plasma.

What factors increase oxygen release from hemoglobin?

Low oxygen levels, high CO2 levels, increased acidity, and higher temperatures enhance oxygen release.

How is carbon dioxide transported in the blood?

CO2 is transported dissolved in plasma (7%), bound to hemoglobin (23%), or as bicarbonate ions (70%).

What are the three forms of carbon dioxide transport?

Dissolved in plasma, bound to hemoglobin (carbaminohemoglobin), and as bicarbonate ions.

What is the bicarbonate buffer system, and how does it help maintain pH?

It regulates blood pH by converting CO2 into bicarbonate (HCO3-) and hydrogen ions (H+), helping to balance acidity.

How does cigarette smoking damage the respiratory system?

Smoking paralyzes cilia, increases mucus production, leads to chronic bronchitis, destroys alveoli, and raises lung cancer risk.

What is chronic bronchitis, and what causes it?

Chronic bronchitis is long-term inflammation of the airways, usually caused by smoking or air pollution.

What is emphysema, and how does it affect respiration?

Emphysema destroys alveolar walls, reducing surface area for gas exchange and making exhalation difficult.

What is lung cancer, and what are its main risk factors?

Lung cancer is uncontrolled cell growth in lung tissue, mainly caused by smoking, air pollution, and genetic factors.

How does environmental tobacco smoke (ETS) affect nonsmokers?

ETS increases the risk of lung cancer, heart disease, and respiratory infections in nonsmokers.

What is the effect of high altitude on respiration?

Lower atmospheric pressure reduces oxygen diffusion, leading to altitude sickness and increased breathing rate.

What is pneumonia, and how does it affect gas exchange?

Pneumonia is a lung infection that causes alveoli to fill with fluid, reducing oxygen exchange.

What is tuberculosis, and how does it impact the lungs?

Tuberculosis is a bacterial infection that forms tubercles in the lungs, thickening the respiratory membrane and reducing gas exchange.

What is atelectasis, and what causes lung collapse?

Atelectasis is the collapse of lung tissue, caused by airway obstruction, injury, or infections.

What is acute respiratory distress syndrome (ARDS)?

ARDS is a severe condition where fluid fills the alveoli, reducing oxygen exchange and leading to respiratory failure.

How does aging affect the efficiency of the respiratory system?

Aging leads to reduced elasticity of lung tissues, weaker respiratory muscles, and a decreased ability to clear mucus.

What changes occur in lung tissue with age?

Alveoli walls thin, bronchioles lose muscle tone, and lung elasticity decreases, making breathing more difficult.

Why do older adults have an increased risk of respiratory infections?

The immune system weakens, cilia become less active, and mucus thickens, making it harder to remove pathogens.

How does the loss of cilia impact the respiratory system?

Cilia help clear mucus and debris; their loss increases the risk of infections and mucus buildup.

What changes in the thoracic cavity affect breathing in older adults?

Stiffening of the rib cage and reduced diaphragm movement make breathing more effortful.