Respiratory System (II) Flashcards
What are the 9 functions of the respiratory system?
- Upon inhalation, draw air into lungs for O2
- To transfer O2 from air into bloodstream
- Acid/base regulation
- Humidification of inspired air
- Thermoregulation
- Defense against environmental contaminants
- To provide sensory input via olfactory cells
- Communication
- To assist in defecation and parturition
What “sweeps” away particles?
Ciliated mucosa
Cilia
Body loses heat by…
Exhaling hot air to cool body
Blood takes CO2 to _____ to become expired
Alveoli
What traps contaminants (bacteria and allergens)?
Mucus
What makes up the roof of the mouth?
Hard palate and soft palate
Acts as a gate and needs to be strong
Epiglottis
What’s the function of the epiglottis?
Closes off trachea when swallowing and holds down soft palate when breathing. Does not close off esophagus
What warms the air?
Concha
What does the trachea have that keeps it open all the time and prevents it from collapsing?
Cartilage rings
What’s the function of the pharynx?
Allows communication between the posterior nares and the larynx.
How big is the pharynx in the adult horse?
15cm
What are two things that can happen when food enters the trachea?
Asphyxia and Pnemonia
_____ are holes in the skull. Makes the skull lighter.
Sinuses
Paralysis usually in the left arytenoid cartilage
Laryngeal hemiplagia
The laryngeal hemiplegia is idiopathic. Meaning?
No one knows the cause
This disease involves the epiglottis. Some horses have a weak epiglottis and their soft palate displaces and goes up which hinders _____.
Dorsal displacement of the soft palate
Hinders breathing
Horses have about _____ branches before arriving at alveoli
40
Which are the smallest blood vessels?
Capillaries
There’s smooth muscle around _____, _____ and _____.
Trachea, bronchi and bronchioles
Irritants causes muscles to _____
Contract
What happens when you breathe in cold air?
Bronchial constriction
Why do alveoli and capillaries have such thin membranes?
To diffuse CO2 and O2
This muscle is extremely important for breathing
Diaphragm
The thoracic cavity has _____ atmospheric pressure which keeps the lungs open all the time.
Negative
What happens when thoracic cavity is punctured?
Lungs collapse
The diaphragm contracts to _____ the pressure. This makes the pressure more _____ and draws air _____.
Decrease the pressure; more negative; draw air in
The diaphragm separates the _____ and _____.
Thoracic and abdominal cavity
The pleural space outside of the lungs aims to
Reduce friction
What shape does the diaphragm have?
Dome shape
The left lung has an area where
The heart rests
You can condition the circulatory system, but not the respiratory system. The nose and trachea have
A maximum amount of oxygen they can bring in
Horses can be conditioned to utilize oxygen better by way of _____. _____ can strengthen, too.
Skeletal and heart muscles
Air in the trachea is more turbulent. Why?
There is less area for it to go through
The air is more placid when it reaches the lungs because there is an increase in
The area - necessary for gas exchange
Can the trachea expand?
No. Only one size!
What are the parts of the upper airway?
Nose, pharynx, larynx
What are the parts of the lower airway?
Tracheobronchial tree (trachea, bronchi, bronchioles) and alveoli
Gas exchange in the _____
Alveoli
The upper airway _____ and _____ the air. Provides _____% of the resistance to air flow.
Warms and humidifies. 60%
Horses are obligate nasal breathers. This means what?
During exercise, horses cannot use their mouths to breathe - they have to breathe through their nose.
How can nasal resistance be decreased during exercise?
Flaring of nares and vasoconstriction of vascular tissue in nose
Lungs have a compliance which means…
They have a certain extent to which they can expand and elasticize
What is the limiting factor once a horse reaches peak performance?
Respiratory tract
Nasal cavity, pharynx and larynx contribute _____% airway resistance
Trachea, bronchi and bronchioles contribute _____%
Upper = 50-70%
Lower = 30-50%
What is the limiting factor for tidal volume in performance horses?
Nasal cavity
Tidal volume is like a tidal wave. It is the volume of air in each _____
Breath
What is the tracheobronchial tree lined by?
Secretory ciliated epithelium
Trachea and bronchi are supported by cartilage to prevent _____
Collapsing
Trachea and bronchi have specialized cells to secrete
Mucus
Tracheobronchial tree is a branching system that delivers air to _____. Horses have _____ branches. Humans have 24.
Alveoli
40
Laminar airflow in bronchioles is _____ for gas exchange. What’s it cause?
Slow; produces no sound so you cannot hear normal lung sounds with a stethoscope
Smooth muscles actively regulates _____ in response to stimuli.
Airway diameter
