Lab 13: Respiration Flashcards
The lateral walls of the nasal cavity have three bony projection
- superior, middle and inferior nasal conchae
* conchae divide the nasal cavity into three passageways
palate
- partition, between nasal cavity + mouth
- hard palate: anterior, rigid due to bone reinforcement
- soft palate: posterior, lacks bone
three regions of the pharynx:
Which regions of the pharynx are also common to the digestive tract?
- nasopharynx: region just above and behind the soft palate
- oropharynx: region posterior to the mouth
- laryngopharynx: region posterior to the larynx
Which regions of the pharynx are also common to the digestive tract?
oropharynx & laryngopharynx
Larynx
- composed of nine pieces of cartilage
- thyroid cartilage - largest, hyaline cartilage, “Adam’s apple”
- epiglottis - elongated flap over layrnx entrance to the (elastic cartilage)
Pathway of Air
Air –> nostrils –> nasal cavity –> pharynx (nasopharynx –> oropharynx –> laryngopharynx) –> larynx –> trachea –> L/R. primary bronchi –> secondary bronchi –> tertiary bronchi –> bronchioles –> terminal brochioles –> respiratory bronchioles –> alveolar ducts –> alveolar sacs –> gas exchange occurs between the air/blood in individual alveoli.
Free movement of the lungs in the thoracic cavity is facilitated by ______
the pleural membranes
How is the ciliated pseudostratified epithelium specialized for its protective function in the respiratory tract?
- Goblet cells: secrete mucus that traps dust/foreign particles
- Cilia: sweep mucus with trapped particles up out of lungs to back of the throat (can cough or swallow it.
- Function: prevent dust / foreign particles from getting into lung tissue.
C-shaped band of cartilage in trachea
What type of cartilage is this band?
- gives support and flexibility to the trachea.
- prevent collapse of the trachea when the esophagus is distended by food
- Hyaline Cart.
Respiratory Membrane
alveolar sacs + capillaries
What type of epithelium is found in the alveoli? What is the function of this epithelium?
simple squamous epithelium: function is diffusion of gasses.
pulmonary ventilation
-types
- Breathing
- movement of air into/out of the respiratory tract.
- involve changes in the volume of the lungs which produce pressure gradients
Types
• inspiration (inhalation): movement of air into respiratory system
• expiration (exhalation): movement of air out of respiratory system.
Intrapleural Pressure
pressure inside the pleura cavity (space between parietal and visceral pleurae)
atmospheric pressure
pressure due to the weight of the air
intrapulmonary pressure
pressure inside the lungs at the alveoli
Experiment: a bell jar model of the lungs
Diaphram changes
Diaphram contracts:
- moved inferiorly and flattens
- volume increases
- pressure decrease (lungs)
- If pressure in lungs is less than in atmophere, air moves down gradient from high (atmosphere) to low pressure (lungs) and lungs inflate
Diaphram Relaxes:
- Into dome shape
- Volume in thoracic cavity decrease
- pressure in lungs increases
- Lungs higher pressure than in atmosphere (moves from lungs [high pressure] down pressure gradient into atmospjere [low pressure])
spirometer
• apparatus used to measure Lung volumes and capacities
Tidal Volume (TV)
- What muscles are involved during normal, quiet inspiration?
- What is an average value for tidal volume?
• tidal volume - The volume of air inspired or expired with each normal, quiet respiration
Results
Approx. 500mL
Muscles: diaphragm, external intracostal muscles
Expiratory Reserve Volume (ERV)
- What is an average value
• expiratory reserve volume - volume of air that can be forcibly expired after a normal expiration
Results
Muscles: abdominal muscles and internal intercostal muscles
Approx. 1200mL male, 800mL female
Vital Capacity (VC)
- What is an average value
- What muscles are involved during forced inspiration?
• Vital capacity - maximum amount of air that can be moved into and out of the lungs from a maximal inspiration to a maximal expiration
Approx. 4800mL males, 3400mL female
Muscle Use During Respiration:
- What muscles are involved during normal, quiet inspiration?
- What muscles are involved during forced inspiration?
- forced expiration
- Normal expiration
Normal Quiet Inspiration
-passive process, no muscle contraction involved
Forced Inspiration
-neck muscles (sternocleidomastoid, scaline) pectoralis minor
Forced Expiration
-abdominal muscles and internal intercostal muscles
Normal expiration
- diaphragm, external extracostal muscles
Inspiratory Reserve Volume (IRV)
• Inspiratory Reserve Volume - volume of air that can be forcibly inhaled after a normal inspiration
IRV = VC - (ERV + TV)
Neck muscles such as sternocleidomastoid and scaling and pectoralis minor
Oxygen is carried in the blood in two ways;
C02 in 2 ways
Oxygen
1) majority (98.5%) is carried bound to the hemoglobin molecules within the red blood cells,
2) the rest is dissolved in the blood plasma
Carbon Dioxide
1) primarily as bicarbonate ions in the plasma (70%),
2) remaining amounts transported bound to hemoglobin and as a gas dissolved in the plasma.
Central chemoreceptors,
- located in the medulla
* respond to increases in pCO2 and hydrogen ion concentration of the cerebrospinal fluid
Peripheral chemoreceptors
- located in the aortic arch and carotid arteries
* respond to increases in pCO2 and H+ and to decreases in pO2, of arterial blood
Why does Respiration rate change when going from sitting to running?
- Partial pressure of CO2 increased at muscle tissue as increase in cellular respiration to produce energy for contraction - stimulates respiratory centre
- Lactic acid after exercise which decreased blood ph also stimulates respiratory centres
- Increase muscle Joint receptor information, therefore increasing respiration rate
Why can you hold you breath longer after after breathing deeply and vigorously for two minutes.
You removed CO2 from lungs and decreased blood partial pressure of CO2, therefore less stimulation of respiratory centre and can hold your breath longer
Breath into a Paper bag for 2 min/
- Increase respiratory rate because partial pressure of CO2 in blood stimulates respiratory centre to increase respiratory
- When you exhale CO2 into the bag it is not removed by atmosphere and you keep re-breathing it
