Respiratory System 2 Flashcards
Diffuse rate proportion to
SA
Concentration gradient
Membrane thickness
Diffusion distance
Factors that influence movement of gases from air into liquid (3)
Pressure gradient
Solubility
Temperature
Upper respiratory tract vs Lower
Conducting vs Respiratory zone
Mouth, nasal cavity, pharynx, larynx
Trachea, bronchi, bronchioles, alveoli
Type I alveolar cells
Type II
Surfactants
Work required for ventilation depends on:
- Elastic properties of the lung and chest wall (compliance and elasticity)
- Resistance to airflow into the pulmonary pathways
Emphysema
Pleural sac:
- Parietal pleura
- Visceral pleura
- Pleural cavity
Mammal ventilation
- Inhalation (5)
- Expiration (5)
Inhalation:
1) Somatic motor neuron innervation
2) Contraction of external intercostals and diaphragm
3) Rib moves outwards and upwards and diaphragm moves down
4) Volume of thoracic cavity increases
5) Air pulled in
Expiration:
1) Innervation stops
2) Muscles relax
3) Ribs and diaphragm return to their original positions
4) Volume of thoracic cavity decreases
5) Air pushed out via elastic recoil of lungs
Types of pressures exerted in thoracic cavity:
1) Intra-alveolar pressure / Intrapulmonary pressure (Ppul)
2) Intrapleural pressure/ Intrathoracic pressure (Pip)
- Negative Pip pressure caused by what forces
Transpulmonary pressure
Pneumothorax
Spirometer
- Can distinguish between what?
Obstructive pulmonary disease (increased airway resistance)
Restrictive disorders (reduced TLC due to disease or fibrosis)
Tidal volume
Factors that impact respiratory cavity
0.5 L
Size, gender/sex, age, physical condition
Dead space:
- Anatomical dead space
- Alveolar dead space
Alveolar ventilation = Ventilation rate x (tidal volume - dead space volume)
Total pulmonary ventilation (TPV) / Minute volume
- 6 L/min or 12-20 breaths per minute
Cardiac output = Heart rate x Stroke volume
Oxygen carrying capacity
Effect on PO2 by binding O2 to hemoglobin (metalloprotein / respiratory pigments)
Respiratory pigments:
- Hemoglobin
- Hemocyanin
- Hemerythrin
Myoglobin
Metal ions; red; Tetramer (two alpha and two beta chains containing heme group)
- Vertebrates, nematodes, annelids, crustaceans, insects
Copper; blue; Multimeric (48 subunits); dissolved in hemolymph
- Mollusks and anthropods
2 iron per subunit; violet-pink; trimeric or octomeric; no heme
- Sipunculids, priapulids, brachiopods, annelids
Monomer; binds one oxygen; type of hemoglobin
- Vertebrate muscle
Oxygen equilibrium curve
P50
Positive vs negative allosteric modulators
Myoglobin curve shape
Cooperativity of binding + hemoglobin curve shape
Oxygen
H+, CO2, 2,3DPG
Hyperbolic
Sigmoidal
Bohr effect
- How to cause shift
- What left and right shift mean
- Effect of temperature and organic modulators (2,3-DPG, ATP, GTP)
How:
- Changing PCO2 of blood
- Changing blood pH
Right: Lower O2 affinity (offloading O2)
Left: Increased O2 affinity (Loading O2)
Increase causes decreased O2 affinity; right shift
Root effect
Decrease in pH causes right shift of oxygen equilibrium curve and reduction in oxygen carrying capacity in blood
- Teleost fish and invertebrates
- Helps deliver O2 to eye and swim bladder
Swim bladder
- Uses bohr and root effect
- Countercurrent flow
3 ways CO2 is transported in blood
Carbonic anhydrase
Chloride shift vs Reverse chloride shfit
7-10% dissolved in plasma
20% bound to globin of hemoglobin (carbaminohemoglobin)
70% transported as bicarbonate ions (HCO3-) in plasma
Catalyzes formation of bicarbonate ions
HCO3- exchanged w/ Cl- with surrounding plasma
- Prevents buildup of bicarbonate
- In systemic capillaries
Reverse: HCO3- moves into blood while Cl- moves out, forming H2CO3 (to be split into CO2 and water)
- In pulmonary capillaries
Haldane effect
Binding of O2 to hemoglobin promotes release of CO2
Hypoventilation vs Hyperventilation
Metabolic acidosis vs alkalosis
Increase in CO2 + elevated PCO2
- Plasma CO2 increases, H+ increases
- pH decreases
- Shift to right
- Hydrogen and bicarbonate conc increases
Breathing too quickly (CO2 leaves too quickly)
- CO2 decreases, pH increases
- Shift to left
- Hydrogen and bicarbonate decrease
Caused by lactic acid accumulation, ketoacids (breakdown of fats/amino acids), loss of bicarbonate
- Hydrogen conc increases, pH decreases
- Shift to left
- Bicarbonate decreases, CO2 increases
- Causes hyperventilation (reduce PCO2)
Caused by loss of H+ from vomiting acid stomach contents or excessive bicarbonate buildup
- H+ decreases, pH increases
- Shifts to right
- Bicarbonate increases, CO2 decreases
- Causes hypoventilation (PCO2 increased) ; corrects pH but increases bicarbonate short term
Central pattern generators in medulla
Pre-Botzinger complex
Chemosensory input importance; regulator?
Parafacial repsiratory group (Pre-I) fires first before Pre-Botzinger complex
Chemoreceptors detect changes in CO2, H+ and O2 (negative feedback loop)
- O2 regulator in water-breathers, CO2 in air-breathers
