What is the approximate ventilation/perfusion ratio in the lungs?
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It is approximately 0.8.
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What is the approximate ventilation/perfusion ratio in the lungs?
It is approximately 0.8.
What is the term for the air reaching the alveoli per minute?
Alveolar ventilation.
What is the force that prevents alveoli from collapsing?
Surfactant
What type of cell is described as having granules and containing cytochrome p450 enzymes for detoxification?
Club cell
What is the effect of thickening of the respiratory membrane?
It increases the diffusion distance.
Which type of hypoxia occurs when there is inadequate blood flow?
Ischemic-Stagnant hypoxia.
Which cell in the bronchiole epithelium has the ability to regenerate and proliferate by division?
Clara (Club) cell.
What are the carotid chemoreceptors sensitive to?
Arterial O2 decrease.
What is the role of Substance P on the Pre-Bötzinger center?
It accelerates respiration.
What is the term for the airways where gas exchange does not occur?
Dead space.
What is the cause of death in CO poisoning?
Shift of the Hb-O2 curve to the left (due to Hb not releasing O2 to tissues).
Which hormone decreases surfactant production?
Insulin
What happens to the oxygen-hemoglobin dissociation curve when CO2 increases?
It shifts to the right.
Why are the dead bodies in CO poisoning pink (light red) in color?
Because there is O2 in the hemoglobin, but it cannot reach the tissues.
What is the epithelial type of the bronchi?
Pseudostratified ciliated columnar.
What parameter indicates the mid-to-small airway obstruction and flow during forced expiration?
FEF 25-75.
Which nerves carry information from peripheral chemoreceptors?
Glossopharyngeal (Hering) and Vagus (Cyon) nerves.
What is the effect of decreased H+ and CO2 on the oxygen-hemoglobin dissociation curve?
It shifts to the left.
What type of hypoxia occurs when there is a lack of hemoglobin to carry oxygen?
Anemic hypoxia.
What are the important characteristics of the bronchioles?
Absence of cartilage, abundant smooth muscle.
Which channel connects the bronchiole to the alveolus without being attached?
Lambert channel.
Which center controls both inspiration and expiration related neurons?
Ventral respiratory group (VRG).
Which receptor is responsible for bronchodilation?
Vasoactive Intestinal Peptide (VIP).
When do primitive alveoli form?
Terminal sac stage.
What is the type of epithelium in the alveoli?
Simple squamous.
What type of cartilage is found in the trachea?
Hyaline cartilage.
What is the term for the ability of a unit change in pressure to cause a change in volume?
Compliance
How is Residual Volume (RV) measured?
Using the helium dilution method and plethysmography.
What is the term for the air expelled after a deep inspiration?
Forced vital capacity (FVC).
What is the normal V/Q ratio in the lungs?
0.8.
Which center provides quiet respiration?
Dorsal neuron group.
What effect does atropine have on the bronchioles?
It blocks muscarinic acetylcholine receptors, dilating the bronchioles.
In which period does surfactant synthesis begin?
Canalicular stage.
What is the epithelium of the bronchioles?
Initially simple ciliated columnar, then simple cuboidal epithelium (non-respiratory bronchioles contain simple cuboidal epithelium).
What type of epithelium lines the trachea?
Pseudostratified ciliated columnar epithelium.
Where are the medullary chemoreceptors located and what stimulates them?
Medullary chemoreceptors are stimulated when the partial pressure of carbon dioxide (pCO2) in the blood increases.
What are the parameters that affect the diffusion rate of gases through the respiratory membrane?
Gas diffusion coefficient, solubility of the gas in the membrane, surface area of the membrane, and thickness of the membrane.
What is the main component of surfactant?
Dipalmitoyl phosphatidylcholine (DPPC)
What is the name for the process of taking chloride from the periphery and releasing it in the lung capillaries?
Chloride shift.
What are the channels present between the bronchioles?
Martini channels.
Where is the center that carries the information of decreased PO2 located?
Nucleus tractus solitaryus.
What is the slow-acting substance of anaphylaxis (SRS) responsible for in the bronchioles?
It constricts them.
Which stage is the first period of respiratory system development?
Pseudoglandular stage.
What is the epithelium type of the bronchi?
Pseudostratified ciliated columnar.
What is found in the vocal cord structure?
Elastic fibers (vocal ligament), stratified squamous epithelium, vocalis muscle.
What is the relationship between P50 value and the green curve on the Hb-Oxygen dissociation curve?
It could be related to the decrease in P50 value.
What is the formula for minute ventilation?
Minute ventilation = Tidal Volume x Respiratory Rate.
How does thickening of the respiratory membrane affect gas exchange in interstitial lung diseases?
Thickening of the respiratory membrane increases the diffusion distance.
Which hormones increase surfactant production?
Thyroid, Cortisol, and Estrogen
What primarily increases the respiratory volume of a young adult engaging in moderate physical activity?
Inspiratory reserve volume.
Where in the lungs is ventilation/perfusion ratio best?
Apex.
Which center works in addition to the quiet respiration center during intense exercise?
Ventral neuron group.
What stimulates peripheral chemoreceptors the most?
Decrease in arterial O2.
Which stage is characterized by the appearance of the blood-air barrier and the initial gas exchange?
Terminal sac stage.
What are found in the olfactory mucosa?
Supporting cells, basal cells, olfactory cells, Bowman's glands (lack of goblet cells).
At which vertebra level do the bronchi bifurcate?
T4.
What is the nerve responsible for quiet respiration?
Phrenic nerve
Which cell secretes surfactant?
Type II alveolar cell
Which volume increase leads to a decrease in vital capacity?
Residual volume.
What type of channels facilitate the inter-alveolar passage?
Alveolar pores.
What ions enter the cell for transmitter release from glomus cells?
Calcium.
What is the reflex that prevents excessive lung stretching and damage?
Hering-Breuer reflex.
From which cell origin are the cartilages of the larynx?
Neural crest.
Which cell in the respiratory epithelium has a neurosensory receptor function?
Brush cell.
What type of epithelium is the true vocal cord?
Non-keratinized stratified squamous epithelium.
What is the expected change in arterial PO2, PCO2, and pH during strenuous exercise in a healthy athlete?
No change (E) in arterial PO2, PCO2, and pH.
What is alveolar ventilation and how is it calculated?
Alveolar ventilation is the amount of fresh air reaching the alveoli per minute and is calculated as (Tidal Volume - Dead Space) x Respiratory Rate.
What does Ferrous iron (methemoglobin) do to the Hb-O2 curve?
Shifts it to the left.
What is the term for the air expelled after a maximum inspiration?
Vital capacity.
Which cells are found in the bronchiolar epithelium?
Cuboidal ciliated cells, clara cells, brush cells, and small granular cells.
What is the most abundant cell in the alveolar epithelium?
Type I pneumocyte (flat alveolar cell).
Which center stimulates inspiration by affecting the quiet respiration center?
Apneustic center.
What conditions stimulate the chemoreceptors related to respiration?
Decrease in oxygen pressure, increase in carbon dioxide pressure, increase in H+ ions (acidosis), decrease in pH, and hypoventilation.
Which stage of lung development continues after birth?
Alveolar stage.
What type of neuron is the olfactory or smell cell?
Bipolar neuron.
Into which bronchus do foreign bodies most commonly enter?
Right bronchus.
What are the histological structures of the trachea?
Lymphoid tissue, Hyaline cartilage, Thick basal membrane, Elastic membrane (Bowman's gland is not present in the olfactory region).
What is the volume of air expelled after a maximal inspiration?
Vital capacity.
Which cell in the alveolar epithelium is responsible for surfactant secretion, detoxification, and division?
Type II pneumocyte (Type II pneumocyte's other names: Great alveolar cell, septal cell).
Which center from the pons delays the closure of the ramp signal?
Apneustic center.
Where does the respiratory system embryologically originate from?
Endoderm.
Where does gas exchange in the respiratory tract begin?
In the respiratory bronchioles.
Which neurons in adult life have the ability to undergo mitosis?
Olfactory bipolar neurons, hippocampal neurons.
What does FEV1/FVC (Tiffeneau index) indicate if it is low?
Obstructive disease (Asthma or COPD).
Which channels close proportionally to hypoxia?
Potassium channels.
Where are the pacemaker cells located?
In the pre-Bötzinger complex.
Which part of the respiratory system is lined with ectodermal epithelium?
Vestibulum.
What is the stem cell in the respiratory epithelium?
Basal cell.
What type of cartilage is the thyroid, cricoid, and arytenoid cartilage?
Hyaline cartilage.
When does central cyanosis occur?
When deoxygenated Hb is more than 5 gr/dl (in arterial blood).
What are the stages of embryological development of the lungs?
Pseudoglandular, canalicular, terminal sac, alveolar stage.
What is the neuroendocrine cell in the respiratory epithelium?
Granular cell (Kulchitsky cell).
What is the epithelium of the false vocal cord?
Pseudostratified ciliated columnar epithelium.
What is the role of retinoic acid at the beginning of development?
It plays a role in the beginning of development.
What happens in the absence of dynein in ciliated cells?
Kartagener syndrome occurs.
What gland is found in the olfactory region?
Bowman glands.
