Respiratory System - Notes Flashcards
What are the 4 types of respiration?
Breathing
External Respiration
Internal Respiration
Cellular Respiration
What is external respiration?
The exchange of CO2 and O2 between the air and the blood in the lungs
What is internal respiration?
Exchange of gases between blood and tissue fluid
Think Capillary Bed!
What is cellular respiration?
at the cellular level where ATP is made by mitochondria.
List the important structures of the respiratory system
Trachea
Bronchus
Bronchioles
Lung
Ribs
Diaphragm
What is the pathway of air during external respiration?
air goes to:
The Nasal Cavity
Pharynx
Larynx
Trachea
Bronchus
Lung
Bronchioles
Alveoli
What are Alveoli?
Tiny sacs at the end of the bronchioles
High total surface area - which provides a greater area for diffusion of gases
Supplied with many capillaries - which increases diffusion of gases into the blood
Thin and Moist - which increases diffusion of gases
Lined with a layer of lipoprotein (surfactant) - to prevent the alveoli from collapsing on exhale
What is a normal breathing rate in an adult?
14-20 breaths per minute
What is inspiration?
taking of air in
What is expiration?
the forcing of air out
What are pleural membranes?
The membranes which enclose the lungs
The outer pleural membrane adheres closely to the walls of the chest and diaphragm and the inner is fused to the lungs
The two membranes lie very close to each other separated by a thin film of fluid
Help keep the lungs inflated and allow the lungs to move freely without friction in the thoracic cavity
Where do you find cilia?
They line the upper airway (trachea & Bronchi) to help keep the windpipe free of debris.
How does the nervous system control breathing?
During inspiration, the respiratory center in the medulla oblongata stimulates the rib (intercostal) muscles and the diaphragm to contract.
Nerve impulses from the expanded lungs then inhibit the respiratory center
Lack of stimulation causes the rib muscles and diaphragm to relax and expiration follows
When the concentration of CO2 and H+ ions (also HCO3- ions) reach a certain level in the blood, the breathing center in the medulla oblongata is stimulated so inspiration will occur.