Secondary
- Anatomy
- epiglottis (cover trachea and prevent food from into), larynx (voice box)
- trachea - main trunk of the trees
- anaphylaxis
- there's ciliated cells secreting mucus
- bronchi - two main branch
- bronchioles
- Alveoli - site of gas exchange (O2/CO2) - external respiration; loaded with capillaries;
- grape-like clusters: increased surface area for gas exchange
- rich in capillary: increased blood flow for gas exchange
- lipoproteins (cholesterol) - helps maintain alveolar shape, prevents collapse at low pressure - tissue-thin, compliance); surfactant (lower surface tension for easier gas exchange); keeps the airway dry but the membrane moist
- Cilia - hair-like (not hair) structures within the trachea, bronchi, larynx and nasal cavity
- sweep up mucus-coated debris; to be coughed up, swallowed or expelled (expectorated); move mucus towards glottis
- taste bud in the lung to tell the brain there's food not supposed to inside
- Nose hair - filters incoming air of dust, debris, soot etc; can warm and moister inhaled air
- blow nose before COVID test
- Lung - right side 2 lobes; left side 3 lobes for surface area; floating inside the Intrapleural fluid
- Diaphragm
- Intercostal muscles - ribs muscles
- Pleural membrane
- Intrapleural fluid - between Pleural membrane and Lung
- even out pressure on the lungs - all parts compressed evenly; liquid non-compressible
- reduce friction (as lubricant) during inhalation - secondary fx
- Mechanics of Breathing
- nervous control: medulla oblongata; within upper parts called pons
- babies may stop breathing for up to 45s
- breathing centre, or heart rate control
- chemoreceptors within the aortic arch and carotid arteries monitor bicarbonate ions HCO3- and H+ levels - testing the blood for its CO2 and pH content
- more HCO3- = more CO2 in blood due to increased rate of cell respiration - increased need for O2 - increased respiratory rate
- peripheral chemoreceptors (at carotid bodies) also monitor for low O2 levels, and signal the brain on respiratory rate increase = secondary mechanics
- pH
- high CO2 levels lower the pH (hypercapnia -nia state of being) - the brain's blood vessels to dilate - increase blood flow and supply of oxygen
- low CO2 raises the pH (hypocapnia) - brain's blood vessels to constrict
- Hyperventilation
- breathe too deeper or too rapidly; exhale too much CO2 (e.g. under stress); not enough of CO2 - blood pH - alkaline - blood vessels constrict reducing the flow of O2 - rapid shallow breathing - treatment to take slow, deep breathes
- not too much CO2, nor too little O2 #exam
- Mechanics
- Inhalation (inspiration) #exam
- Medulla oblongta - stimulate the (+ the heart rate)
- diaphragm to contract - pulling downward on the lung
- intercostal muscles to contract - lifting the ribs up and outward
- gas in a larger volume - lower atm pressure = negative pressure - air drawn into the lung (like the vacuum) to fill partial vacuum
- increased thoracic cavity volume - decreased intra-thoracic pressure
- Exhalation (expiration)
- stretch receptors in the alveoli signal Medulla oblongta)
- diaphragm relax - lift up and resume normal relaxes dome shape
- intercostals relax - ribs fall down and inward
- increased pressure = positive pressure (uni) - air squeezed out
- Elevation impact on breathing - higher altitude, air pressure drops - can't breathe in - harder to breathe in; muscular needs more airs (helicoptor rotor may not work in Everest)
- deep mine, harder to breathe out - exhale
- How the body might acclimate to high altitude - produce more red blood cells (long-term); increase resp. rate; increased cardiac output
- People living at higher altitude - can go on lower - patterns of adaption to high-altitude hypoxia
- Air flow
- TLC - total lung capacity, 6L M; 5L F
- TV - tidal volume - amount of air moving in and out the lung during each respiratory cycle - 500 ml
- RV - residual volume - 1L
- IRV - forced inhalation volume
- ERV - forced exhalation volume
- VC - vital capacity = IRV + TV + ERV (minus negative value) = TLC - RV
- VO2 max - max rate of O2 consumption - swimmer, speed skater
- Gas exchange
- 5% CO2 dissolved, 25% HbCO2, 70% bicarbonate ions (detected, or tasted by)
- Hb + H+ - reduced Hb (electron gained) - H2O
- CO2 + H2O - H2CO3 (carbonic acid) - HCO3- + H+ (Carbonic anhydrase)
- Hemoglobin - shaped affected by changes in pH and temp.
- lung: pH 7.4, temp 37 C (more basic, alkaline and cooler)
- tissues: pH 7.38 and 38 C (more acidic and warmer)
- Bohr effect (Niels Bohr's father Charles Bohr)
- lower pH, the greater Hb affinity is for CO2 and facilitate the release of O2 ino the tissue
- less CO2 raises pH and decrease Hb affinity for CO2 and increase Hb affinity for O2; and facilitate the release of CO2 in exchange O2 at lung
- PO2 - partial pressure
- Hb dissociation curve
- in order to obtain -95% saturation
- at pH 7.6 requires a pO2 of just 5 kPa (100km/5L fuel)
- at pH 7.2 requires a pO2 of 12 kPa
- Hb lesser affinity for O2 - low pH, high temp, PO2 and DPG (hormone)
- decrease of Hb - acidic plasma/tissue
- if pleural membrane punctured - lung could collapse
- Test
- oxygen dissolves better in liquids than in air, and thus does not leave the lungs
- carbonic anhydrase speeds up the conversion of carbonic acid to carbon dioxide and water; not dissolved in plasma; in red blood cell
- inhaling particles such as silica, coal dust and asbestos can lead to pulmonary fibrosis
- running for a long time can cause decreased pH during internal respiration
- nasal cavities empties into the nasopharynx
- The pleural membranes function to maintain the negative pressure of the pleural cavity
Kaplan
MeSH
- Larynx [A04.329]
- Lung [A04.411]
- Nose [A04.531]
- Pharynx [A04.623]
- Pleura [A04.716]
- Respiratory Mucosa [A04.760]
- Trachea [A04.889]
BIOL235
- 23.1 Overview of the respiratory system, p. 789
- define the steps that occur during respiration.
- The steps involved in respiration
- define the respiratory system.
- Components of the respiratory system
- explain how the respiratory organs are classified structurally and functionally. @@
- 23.2 The upper respiratory system, p. 791
- describe the anatomy and histology of the nose, pharynx, and associated structures, and (larynx, trachea, bronchi, and lungs).
- identify the functions of each respiratory system structure.
- 23.3 The lower respiratory system, p. 794
- identify the features and purpose of the larynx.
- list the structures of voice production.
- The structures of voice production
- describe the anatomy and histology of the trachea.
- identify the functions of each bronchial structure.
- Lungs
- Patency of the respiratory system
- 23.4 Pulmonary ventilation, p. 807
- describe the events that cause inhalation and exhalation.
- Pressure changes during pulmonary ventilation
- Other factors affecting pulmonary ventilation
- Breathing patterns and modified breathing movements
- 23.5 Lung volumes and capacities, p. 812
- explain the differences among tidal volume, inspiratory reserve volume, expiratory reserve volume, and residual volume.
- differentiate inspiratory capacity, functional residual capacity, vital capacity, and total lung capacity.
- 23.6 Exchange of oxygen and carbon dioxide, p. 813
- explain Dalton's law and Henry's law.
- Gas laws: Dalton's law and Henry's law
- describe the exchange of oxygen and carbon dioxide in external and internal respiration.
- External respiration
- Internal respiration
- 23.7 Transport of oxygen and carbon dioxide, p. 816
- describe how the blood transports oxygen and carbon dioxide.
- Oxygen transport
- Carbon dioxide transport
- Summary of gas exchange and transport in lungs and tissues
- 23.8 Control of breathing, p. 822
- explain how the nervous system controls breathing.
- Respiratory center
- Regulation of the respiratory center