ECU BIOL 2150 Exam 4 Training
Questions With Solved Solutions.
Lobules - Answer hexagonal shaped
connective tissue surrounds lung tissue
-each served by a large bronchiole
-black in smokers
Stroma - Answer rest of lung tissue
-mainly elastic connective tissue
-soft, spongy
Pulmonary Circulation - Answer -delivers de-oxygenated blood for oxygenated in pulmonary
capillaries
-returns blood to heart via pulmonary veins
-large volume, low pressure
Bronchial Circulation - Answer -low volume, high pressure
-is blood supply to lung tissue
-branches from aorta --> hilus --> runs along bronchi
-supplies all lung tissue except:
Alveoli (supplied by pulmonary circulation)
There are many anastomoses between? - Answer the bronchial and pulmonary circulation
systems
so most blood in the bronchial circulation - Answer returns to the hear via the pulmonary
veins
Parasympathetic nerve supply - Answer bronchial constriction
sympathetic nerve supply - Answer rare
,Parietal Pleura - Answer -covers inside thoracic wall and top of diaphragm
-around heart and between lungs
-doubles over to become Viseral Pleura
Viseral Pleura - Answer covers outer walls of lungs
Pleural cavity - Answer space between parietal and visceral pleura
Pleura secrets fluid into cavity - Answer allow frictionless movement of lungs inside thorax
Pleurisy - Answer lack of fluid due to inflammation of pleura --> friction --> pain
pleural fluid acts like - Answer glue
produces a surface tension that - Answer bonds pleura together
but slide over each other easily - Answer as a result lungs going tightly to thorax wall
Air flow - Answer movement of air into and out of lungs occurs when the volume in thoracic
cavity changes
pressure changes are described relative to atmospheric pressure = - Answer 760 mmHg
Inspiration - Answer at rest
dome shaped diaphragm contracts - Answer moves downward --> increases volume of thorax
external intercostal muscles - Answer contract lifting rib cage
Intrapulmonary Pressure P(alv) - Answer -rises and falls with the phases of breathing
, -intrapleural pressure is always NEGATIVE
Why is intrapleural pressure always negative? - Answer two forces pull lungs away from thorax
and pull visceral pleura away from parietal pleura
1. elasticity of lungs causes lungs to recoil to smallest size
2. surface tension of alveolar fluid acts to collapse alveoli
These two forces want to do what? - Answer separate visceral pleura from parietal pleura, but
fluid (pleural) is strong
-cohesive bonds secure pleura together
-opposing forces instead cause negative intrapleural pressure
what happens if Pip = Palv or Patm - Answer lung wall collapse pneumothorax (atelectasis)
Pulmonary Ventilation - Answer Lung ventilation is based on Boyles Law P1V1 = P2V2
-pressure of gas varies inversely with its volume
-therefore as volume increases, pressure decreases
-if volume decreases, pressure increases
Inspiration - Answer -Diaphragm contracts
--moves downward and flattens --> increases height of thoracic cavity
-external intercostal muscles contract
-lifts rib cage upward and outward --> increase diameter of thorax
-volume of thorax increases by 500 ml
-Palv drops 1mmHg (vacuum)
-air rushes in thru nostrils - 500 ml
-when Palv = Patm inspiration ends
-Pip is now -6 mmgHg below Patm (754 mmHg)
Expiration - Answer in resting individuals is passive
-natural elasticity of lungs reduces lung volume as inspiratory muscles relax
-diaphragm --> dome shaped
Questions With Solved Solutions.
Lobules - Answer hexagonal shaped
connective tissue surrounds lung tissue
-each served by a large bronchiole
-black in smokers
Stroma - Answer rest of lung tissue
-mainly elastic connective tissue
-soft, spongy
Pulmonary Circulation - Answer -delivers de-oxygenated blood for oxygenated in pulmonary
capillaries
-returns blood to heart via pulmonary veins
-large volume, low pressure
Bronchial Circulation - Answer -low volume, high pressure
-is blood supply to lung tissue
-branches from aorta --> hilus --> runs along bronchi
-supplies all lung tissue except:
Alveoli (supplied by pulmonary circulation)
There are many anastomoses between? - Answer the bronchial and pulmonary circulation
systems
so most blood in the bronchial circulation - Answer returns to the hear via the pulmonary
veins
Parasympathetic nerve supply - Answer bronchial constriction
sympathetic nerve supply - Answer rare
,Parietal Pleura - Answer -covers inside thoracic wall and top of diaphragm
-around heart and between lungs
-doubles over to become Viseral Pleura
Viseral Pleura - Answer covers outer walls of lungs
Pleural cavity - Answer space between parietal and visceral pleura
Pleura secrets fluid into cavity - Answer allow frictionless movement of lungs inside thorax
Pleurisy - Answer lack of fluid due to inflammation of pleura --> friction --> pain
pleural fluid acts like - Answer glue
produces a surface tension that - Answer bonds pleura together
but slide over each other easily - Answer as a result lungs going tightly to thorax wall
Air flow - Answer movement of air into and out of lungs occurs when the volume in thoracic
cavity changes
pressure changes are described relative to atmospheric pressure = - Answer 760 mmHg
Inspiration - Answer at rest
dome shaped diaphragm contracts - Answer moves downward --> increases volume of thorax
external intercostal muscles - Answer contract lifting rib cage
Intrapulmonary Pressure P(alv) - Answer -rises and falls with the phases of breathing
, -intrapleural pressure is always NEGATIVE
Why is intrapleural pressure always negative? - Answer two forces pull lungs away from thorax
and pull visceral pleura away from parietal pleura
1. elasticity of lungs causes lungs to recoil to smallest size
2. surface tension of alveolar fluid acts to collapse alveoli
These two forces want to do what? - Answer separate visceral pleura from parietal pleura, but
fluid (pleural) is strong
-cohesive bonds secure pleura together
-opposing forces instead cause negative intrapleural pressure
what happens if Pip = Palv or Patm - Answer lung wall collapse pneumothorax (atelectasis)
Pulmonary Ventilation - Answer Lung ventilation is based on Boyles Law P1V1 = P2V2
-pressure of gas varies inversely with its volume
-therefore as volume increases, pressure decreases
-if volume decreases, pressure increases
Inspiration - Answer -Diaphragm contracts
--moves downward and flattens --> increases height of thoracic cavity
-external intercostal muscles contract
-lifts rib cage upward and outward --> increase diameter of thorax
-volume of thorax increases by 500 ml
-Palv drops 1mmHg (vacuum)
-air rushes in thru nostrils - 500 ml
-when Palv = Patm inspiration ends
-Pip is now -6 mmgHg below Patm (754 mmHg)
Expiration - Answer in resting individuals is passive
-natural elasticity of lungs reduces lung volume as inspiratory muscles relax
-diaphragm --> dome shaped
