Breathing and Gas Exchange. Flashcards
Respiratory Bronchioles are connected to alveoli along ______ _______.
Alveolar Ducts.
Where do alveolar ducts end?
At alveolar sacs.
Each alveolus has an extensive network of ____ and is surrounded by elastic fibres.
Capillaries.
What is found around bronchioles?
Smooth Muscle.
What is the smooth muscle around the bronchioles regulated by?
It’s regulated by Autonomic Nervous System (ANS).
How does the ANS regulate the smooth muscles around the bronchioles?
- It controls the diameter of the bronchioles
- It controls the airflow and resistance in the lungs.
________ is caused by sympathetic ANS Activation.
Bronchodilation.
What does bronchodilation do?
It reduces resistance.
What is Bronchoconstriction caused by?
Parasympathetic ANS Activation.
In Bronchoconstriction what is released?
Histamine.
_______ increases resistance in the lungs and is often caused by having an allergic reaction.
Bronchoconstriction.
What condition results from excessive stimulation (with sensitive and swollen airways) and bronchoconstriction (severely restricting airflow)?
Asthma.
Allergens and Irritants are triggers of ________.
Asthma.
Name some examples that would restrict airflow.
- Narrowed Airway
- Tightened Muscles
- Inflamed/thickened airway wall
- Excessive mucous.
What is the respiratory membrane?
The thin membrane of alveoli across which gas exchange takes place.
The _____ membrane; where gas exchange takes place, has 3 layers.
Respiratory
Name the 3 layers of the respiratory membrane.
- Squamous Epithelial Cells
- Endothelial Cells
- Fused basement membranes.
What do the squamous epithelial cells line?
The alveolus.
In the respiratory membrane, what do the endothelial cells line?
They line an adjacent capillary .
Where is the Fused Basement Membranes Layer found?
Between the alveolar and endothelial cells.
Is the respiratory membrane thick or thin?
Very Thin (for gas exchange).
What occurs across the respiratory membrane?
Diffusion/ Gas Exchange.
A network of what surrounds each alveolus?
A network of Capillaries.
A capillary network surrounds each _____, as part of the _________ membrane.
Alveolus, Respiratory.