Respiratory System Flashcards
Define respiration
process of gas exchange in which organisms exchange CO2 and oxygen with their environment.
what is the correlation btwn the respiratory system and cellular respiration
- they work together but function independently
- aerobic cellular respiration requires oxygen to break bods of glucose
- respiratory system is needed to obtain more oxygen and eliminate co2
what are the 3 stages of respiration
- pulmonary ventilation (breathing)
- external or pulmonary respiration
- internal or tissue respiration
what are the 2 parts of pulmonary ventilation
inspiration
expiration
Describe Inspiration
- inhalation
- fill the spaces of the lungs with air
Describe expiration
- another name for exhalation
- expel the air after gas exchange
Describe pulmonary respiration
gas exchange between the lung spaces and the blood in the lung capillaries
Describe tissue respiration
the exchange of gas between the blood in systemic capillaries and metabolically active cells such as skeletal muscles
Describe the gross anatomy of lungs
- located in the thoracic cavity
- protected by the ribs and sternum
- below the lungs is the diaphragm
- each lung is divided into lobes
- between the lungs and slightly to the left is the heart
Define diaphragm
flat sheet of skeletal muscle that contracts to cause inspiration
List the lobes of the lungs
- right lung has 3 lobes
- left has 2 lobes
List the structures of the respiratory system
- nostrils or external nares
- nasal cavity
- pharynx or throat
- epiglottis
- larynx or voice box
- Trachea
- Bronchi
- Bronchioles
- Alveoli
Describe External nares
-paired openings in the respiratory tract lined with hair for filtering particles
Describe the nasal cavity
- space inside nose
- passageway for air, warms and humidifies the incoming air
- modifies sounds for speech
- olfactory epithelia used for detecting odours
Describe the pharynx
- common passageway for food, air, liquids
- modifies speech for sound
- location of tonsils
Describe the epiglottis
- moveable flap of cartilage over the voice box
- prevents the passage of food and liquid down the wrong way when swallowing
Describe the larynx
- cartilaginous structure leading to the trachea
- location of vocal cords which are responsible for sound production
Describe the trachea
- airway leading to the lungs
- held open by c shaped rings of cartilage
Describe the bronchi
- branches off trachea held open by cartilage plates
- forms bronchial tree
Describe bronchioles
smooth muscles in walls to regulate diameter
Describe alveoli
- clusters of blind-ended sacs at the ends of bronchioles
- where gas exchange occurs
- lined with simple squamous epithelium
Describe the airways in the respiratory system
- nasal cavity, trachea, bronchi, and bronchioles lined with ciliated, glandular epithelium with goblet cells which secret mucus
- mucus traps inhaled particles and cilia sweep them up to the pharynx to be swallowed
- walls of smaller vessels, bronchioles may have smooth muscles to regulate their diameter
- larger airways (trachea, bronchi) have cartilage rings or plates to keep them from collapsing
- areas of gas exchange are composed of simple squamous epithelium only
- includes alveoli, alveolar ducts, respiratory bronchioles
Describe the respiratory membrane
- gas exchange occurs btwn alveolar spaces and the capillaries surrounding the alveoli. These gasses cross layers of tissue called the respiratory membrane
- Many elastic fibres surround the alveoli
List what the respiratory membrane tissue consists of
- thin alveolar simple squamous cell
- thin alveolar basement membrane
- basement membrane of the capillary endothelial cells
- endothelial cells of capillaries
What factors make the respiratory membrane a very efficient gas exchange site
- large surface area - 750million /lung
- moist
- vascularized-many capillaries
- thin- squamous cells involved
- partial pressure gradient similar to concentration gradient
How does the transportation of oxygen work in the respiratory system
- oxygen is transported by the cardio system from the lunge to tissues, like skeletal muscles for cellular respiration
- occurs from left side of the heart from the left ventricle
- oxygen is not very soluble in water so most of it is transported in the blood bound respiratory pigments
- the brain and heart myst have oxygen to survive
what are respiratory pigments
proteins which contain metal ions to which oxygen binds
What is hemoglobin
a respiratory pigment found in red blood cells that contain iron
Describe the transport of carbon dioxide
- co2 is produced in the tissues by cellular respiration
- hemoglobin transport some co2 when oxygen leaves
- co2 can dissolve in plasma
- bicarbonate ions is the main method of transportation found within plasma
- results in formation of acidic H+ ions
What is hyperventilation
- fast breathing rate
- assists in eliminating co2 from plasma
What happens when we hold our breaths
- our bodies retains co2 for a short while
- reflexes activities if levels become to high in the plasma
How does ventilation function
- inspiration, inhaling, contracts diaphragm
- expiration, exhaling, relaxes the diaphragm
What happens to the diaphragm during inspiration
- contracts which mean it drop, increases the volume of the thoracic cavity
- causes pressure to drop, below atmospheric pressure
- negative pressure ventilation
- air is sucked in through the external nares into the lungs to equalize the pressure
- lung tissue expands, stretching elastic fibers
What happens to the diaphragm during expiration
- volume of the thoracic cavity decreases as diaphragm rises
- elastic fibers recoil back to shorter resting lengths
- increases the pressure in the thoracic cavity higher than atmospheric pressure
- air flows out of equalize pressure again
Describe the differences in atmospheric pressure during ventilation of the lungs
- atmospheric pressure always 760mm Hg
- at rest atmospheric pressure is equal to alveolar pressure = 760mm Hg
- during inhalation, alveolar pressure = 758mm Hg
- during exhalation, relaxation, alveolar pressure - 762mm Hg
