A&P Test 2 Overview

At maximal inspiration, the lungs can hold what approximate volume of air?

6000ml (TLC)

At maximal inspiration followed by a maximal expiration, what approximate volume of air can be moved?

4800ml (VC)

After maximal expiration, what appoximate volume of air remains in the lungs?

1200 (residual volume)

At the end of a normal passive exhalation what appoximate volume of air reimains in the lungs

2400 (FRC)

Starting from the end of a normal exhalation what apporoximate volume of air is inhaled?

3600 (IC)

Beyond a normal tidal inhalation, what approximate volume of air can still be inhaled?

3100ml (IRV)

Beyond a normal tidal exhalation what apporximate volume of air can still be forcefully exhaled?

1200ml ( ERV)

During quiet normal breathing, what approximate volume of air can still be inhaled or exhaled with each breath?

500ml (Vt)

TLC-VC=

RV

VT+IRV=

IC

IC+ERV=

VC

ERV+RV=

FRC

What is the primary function of the frontal sinus in the upper airway?

lightens the skull and helps warm and humidify inspired air

what role does the sphenoidal sinus play in respiration and skull anatomy?

contributes to air warming and humidification

what is the function of the external nares during inspiration?

serves as an entry point for inspired air into the nasal cavity

How does the nasal septum contribute to effective airflow through the nasal cavity

divides the nasal cavity and directs airflow evenly through both nostrils

how do the nasal turbinates affect airflow and air conditioning during inspiration?

increase turbulent low to enhance warming, humidification, and filtration

What is the function of the hard palate in separating the oral and nasal cavity?

it separates both the nasal cavity and oral cavity

how does the soft palate function during swallowing and breathing?

elevates during swallowing to prevent entry into the nasopharynx

what role does the uvula play during swallowing and speech?

helps the soft palate in sealing the nasopharynx

What is the role of the oral cavity in respiration?

serves as an alternate airway of breathing

What is the primary function of the pharyngeal tonsils (adenoids) in the upper airway?

provide immune defense by trapping pathogens

What is the function of the Eustachian tube in relation to the nasopharynx?

Equalizes pressure between the middle ear and nasopharynx and drain liquid out the middle ear

What is the function of the nasopharynx in respiration?

Conducts air from the nasal cavity to the oropharynx

How does the oropharynx function as a shared pathway?

Serves as a common passageway for air and food

What is the function of the lingual tonsil in airway defense?

Provides immune protection at the base of the tongue

What is the role of the epiglottis during swallowing?

Prevents aspiration by covering the glottis

What is the function of the laryngopharynx in directing airflow?

Directs air to the larynx and food to the esophagus

What is the function of the hyoid bone in airway support?

Supports the tongue and larynx to help keep the airway open ( doesnt attach to anything ) floating bone

How do the vocal cords regulate airflow and protect the airway?

Open for breathing, close for phonation and airway protection

What is the function of the thyroid cartilage in the larynx?

Protects the vocal cords and maintains laryngeal structure

Why is the cricoid cartilage critical for airway patency?

It is the only complete cartilage ring maintaining an open airway

What is the primary function of the trachea in the respiratory system?

Conducts air to and from the lungs

What are the 4 paranasal sinuses

Frontal , ethmoid, maxillary, and sphenoid

What is the function of the ethmoid sinus?

Warm/humidify air and protect nearby structures

What is the function of the frontal, maxillary, and sphenoidal sinuses?

Air conditioning, skull lightening, voice resonance

What is a pleural effusion and where does it typically come from?

Fluid accumulation in the pleural space, most commonly due to heart failure (CHF), infections, or fluid from surgery

Why does the right hemidiaphragm sit higher than the left ?

Because the liver sits on the right side

Why does the left hemidiaphragm sit lower than the right ?

Because the heart and stomach sits on the left side

What does the sympathetic nervous system do to the heart and bronchial smooth muscle?

Activation of β1 increases HR (tachycardia) and β2 receptor causes bronchial smooth muscle relaxation (bronchodilation)

How do the beta receptors act on the intestinal motility?

Beta-adrenergic receptors, mainly β2, decrease intestinal motility (slower GI movement)

What does the parasympathetic nervous system do to the lungs?

Parasympathetic stimulation causes bronchcoconstriction which increases mucus production

how does atropine counteract parasympathetic stimulation?

Atropine counteracts parasympathetic stimulation by acting as an anticholinergic (parasympatholytic) drug that blocks muscarinic receptors, preventing acetylcholine from binding. This results in bronchodilation, increased heart rate, and decreased secretions.

What do the pores of Kohn do?

Small openings by the alveoli allow collateral ventilation

help equalize pressure between alveoli

allow air to move from one alveolus to another

help keep alveoli open if an airway is blocked

What is pulmonary surfactant?

Pulmonary surfactant is a phospholipid-protein substance

which cells produce surfactant?

produced by Type II alveolar cells.

How does surfactant affect work of breathing and elastance?

Its purpose is to reduce surface tension, which decreases the work of breathing, decreases elastance, and increases lung compliance.

What is external respiration?

The exchange of gases between the lungs and blood that happens in the alveoli of the lungs.

What is internal respiration?

The exchange of gases between the blood and the bodys tissues that happens in the capillaries of the tissues/organs

What is the mucociliary system

The lungs’ main defense mechanism. That is located in the conducting airways, which are used to trap, move, and remove inhaled particles.

What is cilia?

Tiny hair-like structures on the surface of epithelial cells that moves mucus upward toward the throat.

What is the mucus layer

Produced by goblet cells that has two layers Gel and Sol

What is the GEL layer?

thick, sticky and traps particles and microorganisms

What is the SOL layer?

Thin, watery traps particles and microorganisms

What stimulates goblet cells to release mucus?

smoking

dust

pollutants

fumes

bacteria viruses

Acetycholine

vagal stimulation

histamine

Are submucosal glands under direct nerve innervation?

Submucosal glands are under direct autonomic (primarily parasympathetic) nerve innervation, whereas goblet cells are not.

What happens to the mucociliary system when you’re dehydrated?

Dehydration thickens mucus, impairs ciliary function, and reduces mucociliary clearance.

The sol layer becomes thinner

The gel layer is more viscous

Cilia is trapped

secretions accumulate

dehydration effect on cilia

Dehydration decreases ciliary beat frequency and can stop ciliary movement altogether.

Out of the two main stem bronchi which one has a sharper angle?

Left mainstem bronchus

Which mainstem bronchi is more likely to be intubated accidentally?

The right because it lines up more directly with the trachea

Which mainstem bronchi are more likely to receive aspirated objects?

The right bronchus

Which accessory muscles are used during inspiration?

Sternocleidomastoid, scalenes, and external intercostals

Sometimes pectroalis major/minor and trapezius

Which accessory muscles are used during expiration?

None

During a forceful exhalation which muscles are being used?

Abdominal muscles:

• Rectus abdominis

• External obliques

• Internal obliques

• Transversus abdominis

Internal intercostals

What is the primary function of the upper airway?

Condition and protect inspired air

• Warm the air

• Humidify the air

• Filter particles

• Protect the lower airway (cough, gag, epiglottis)

What is the primary function of the lower airway?

Gas exchange

That means:

• Oxygen enters the blood

• Carbon dioxide is removed

• Conduct air to the alveoli

• Mucociliary clearance (in conducting portion)

Where is the vast majority of gas exchange?

In the alveoli

Which bronchial pathway is the FIRST place gas exchange can occur?

The respiratory bronchioles

Where does the conducting passageway end?

At the terminal bronchioles

What is compliance?

Compliance is how easily the lungs (or chest wall) stretch or expand.

What is the compliance formula?

(C) = ΔV / ΔP

What is elastance?

The tendency of the lungs to recoil back to their original shape after being stretched.

What is the elastance formula?

(E) = ΔP / ΔV

If you needed to do an emergency airway, where can you puncture in the neck?

The cricothyroid membrane

Where does the upper airway/ conducting zone end and start?

Start:Nose and mouth

End: Larynx

Where does the lower airway / respiratory zone end and start?

Start: Below the vocal cords/ trachea

End: Alveoli

Do beta cells decrease intestinal motility, and parasympathetic increases intestinal motility?

Yes which can cause diarrhea

When a person is pursed lipped breathing, what are they trying to do?

Create back pressure during exhalation to keep small airways open, reduce air trapping, and improve ventilation. (COPD pt)

What is the narrowest point of an adult airway?

The vocal cords (glottis) in the larynx

What is dynamic compression?

Collapse of airways during forced exhalation when pleural pressure exceeds airway pressure.

What is equal pressure point (EPP)

The point along the airway where alveolar pressure equals pleural pressure during forced exhalation.

What does the phrenic nerve do?

controls the diaphragm for inspiration and provides sensory input from the central diaphragm, pleura, and pericardium.

What can a pneumothorax do

allows air into the pleural space, causing lung collapse, impaired ventilation, and, in tension cases, mediastinal shift with cardiovascular compromise.

When is racemic epinephrine mainly used for?

For the treatment of upper airway swelling/obstruction, especially stridor from croup or post-extubation airway edema. Which causes a vasoconstriction given every 2 hours