Voice Study Quiz 1

(Respiratory A&P, Laryngeal A&P, Evaluation of Voice Disorders)

What is breathing?

A highly controlled and intricate process that leads to gas exchange and sets the stage for phonation (e.g., voicing)

The process of breathing is driven largely by pressure differentials and the actions of muscles

Most basic elements of breathing:

• Rib cage

• Diaphragm

Lungs

What is the respiratory system?

A group of structures that work together to carry out respiration (breathing).

What types of structures make up the respiratory system?

Bones/cartilages, ligaments, muscles, and organs.

What are the major structures of the respiratory system?

Upper airway, nose/nasopharynx, mouth/oropharynx, laryngopharynx, larynx, trachea, lungs, rib cage, diaphragm.

What are three sections of the pharynx?

Nasopharynx → Oropharynx → Laryngopharynx

🧠 Easy way to remember the pathway

Think of air traveling:

Nose/Mouth → Pharynx → Larynx → Trachea → Lungs

And the rib cage + diaphragm help with the mechanics of breathing.

What is the trachea?

A cartilaginous airway that carries air from the nose/mouth to the lungs.

What is the trachea made of?

16 cartilaginous rings + various tissue types.

What is the carina?

The point where the trachea splits into the right and left mainstem bronchi.

What is a bronchus?

A branch of the airway that carries air into the lungs.
Plural = bronchi

Where do the mainstem bronchi enter the lungs?

At the hilum.

What happens to the bronchi after entering the lungs?

They subdivide into smaller airways until reaching the alveoli.

What are alveoli?

The terminal units of the airway where the airway ends.

🧠 Memorize the pathway

Trachea → Carina → Right & Left Mainstem Bronchi → Smaller branches → Alveoli

Think:

T → C → B → A
Trachea → Carina → Bronchi → Alveoli

What are alveoli?

Tiny air sacs at the end of the airway, surrounded by pulmonary capillaries.

What is the main function of the alveoli?

Gas exchange between the air and blood.

What happens to oxygen (O₂) in the alveoli?

O₂ diffuses from the alveoli → capillaries → bloodstream → body.

What happens to carbon dioxide (CO₂)?

CO₂ moves from the blood → alveoli → is exhaled.

What are the lungs?

The primary organs of respiration. They are made of elastic tissue that inflates and deflates to move air.

How many lobes does the right lung have?

3 lobes:

• Right Upper Lobe (RUL)

• Right Middle Lobe (RML)

• Right Lower Lobe (RLL)

How many lobes does the left lung have?

2 lobes:

• Left Upper Lobe (LUL)

• Left Lower Lobe (LLL)

How does the right mainstem bronchus differ from the left?

The right is shorter, wider, and more vertical.

How does the left mainstem bronchus differ from the right?

The left is longer, narrower, and more horizontal.

Why is the left lung smaller than the right?

To make room for the heart.

Clinical significance of right mainstem bronchus?

Straight alignment with the trachea makes foreign objects much more likely to enter and get stuck in the right lung.

What is the thorax?

The anatomical region between the neck and abdomen.

What makes up the thorax?

Thoracic vertebrae, ribs, sternum, muscles, and other tissues.

What is the chest cavity?

The space inside the thorax that surrounds and protects the lungs, heart, and other structures.

What is the clavicle?

The collarbone.

What is the clavicle important for in respiration?

It provides an attachment site for respiratory muscles.

What muscles attach to the clavicle?

Trapezius, pectoralis major, and sternocleidomastoid (SCM).

What is the sternum?

The breastbone.

What are the 3 parts of the sternum?

Manubrium → Corpus (body) → Xiphoid process

What is the manubrium?

The top portion of the sternum; attachment for ribs 1–2.

What is the corpus/body?

The middle portion; attachment for ribs 2–7.

What is the xiphoid process?

The smallest, bottom “tail” of the sternum; attachment site for multiple muscles.

How many pairs of ribs are there?

12 pairs (24 ribs total).

What are ribs 1–7 called?

True ribs — they attach directly to the sternum through their own costal cartilage.

What are ribs 8–10 called?

False ribs — they attach indirectly to the sternum because their cartilage connects to the cartilage of the rib above, ultimately connecting through rib 7.

What are ribs 11–12 called?

Floating ribs — they have no connection to the sternum.

Memorize!

Ribs	Name	Sternum connection
1–7	True	✅ Direct
8–10	False	🔗 Indirect
11–12	Floating	❌ None

What are the 2 types of respiratory muscles?

Inspiratory muscles help with inhalation; expiratory muscles help with exhalation.

What are the major inspiratory muscles?

Diaphragm + external intercostal muscles

What are the major expiratory muscles?

Internal intercostal muscles + abdominal wall muscles

⭐ MUST KNOW

INHALE → Diaphragm + EXternal intercostals

EXHALE → INternal intercostals + Abdominals

A good little trick:
EXternal = INhale
INternal = EXhale

The words are opposite, which makes them easier to remember! 🫁

What is the diaphragm?

The major/primary muscle of inspiration. #1 muscle for INSPIRATION

What shape is the diaphragm?

Dome-shaped when relaxed.

What happens to the diaphragm during inspiration?

It contracts and flattens, which enlarges the chest cavity and creates a pressure difference that starts inhalation.

What nerve innervates the diaphragm?

The phrenic nerve.

What spinal nerve levels make up the phrenic nerve?

C3, C4, and C5.

“C3, 4, 5 keeps the diaphragm alive.”

Where are the external intercostal muscles located?

In pairs between the ribs.

What happens when the external intercostal muscles contract?

They lift the ribs up and outward, helping with inspiration (inhalation).

What is the main function of the external intercostals?

Raise the ribs → expand the chest cavity → help you inhale.

Where are the internal intercostal muscles located?

Between the ribs, deep to the external intercostals.

How do internal intercostals differ from external intercostals?

They run perpendicular (opposite direction) to the external intercostals.

What happens when internal intercostals contract?

They depress/lower the rib cage during forced exhalation.

What is the main function of the internal intercostals?

Help with forced expiration (exhalation) by pulling the ribs downward.

🧠

Internal Intercostals = EXHALE

Contract → ribs DOWN → forced air OUT

⭐ Compare them

External intercostals:
➡ Ribs UP + OUT → INHALE

Internal intercostals:
➡ Ribs DOWN → FORCED EXHALE

What is the main respiratory role of the abdominal muscles?

They help with exhalation, especially by increasing abdominal pressure.

Think:

Abdominals contract → abdominal pressure ↑ → contents pushed UP → air OUT

What 4 muscles form the abdominal wall?

• Rectus abdominis

• Transversus abdominis

• External abdominal oblique

• Internal abdominal oblique

What does the rectus abdominis do?

Stiffens the ventral (front) midline.

What do the other abdominal muscles do?

They decrease abdominal diameter → increase abdominal pressure → push abdominal contents upward, helping with exhalation.

What are the two phases of respiration?

Inspiration (inhalation) and expiration (exhalation).

What drives air movement in and out of the lungs?

Pressure differences between alveolar pressure and atmospheric pressure.

Air moves because of pressure differences.

What is alveolar pressure?

The pressure inside the alveoli.

What is atmospheric pressure?

The pressure of the environment/surrounding air.

🧠 THE BIG IDEA ⭐ Connect it to the diaphragm

HIGH pressure → LOW pressure

Pressure difference = driving force for breathing

Diaphragm contracts → chest cavity expands → pressure changes → air moves IN

Diaphragm relaxes + expiration muscles → chest cavity decreases → pressure changes → air moves OUT

What causes air to move during breathing?

A pressure difference between alveolar pressure and atmospheric pressure.

What happens during inspiration?

Alveolar pressure < atmospheric pressure → air moves IN.

What happens during expiration?

Alveolar pressure > atmospheric pressure → air moves OUT.

What determines the direction of airflow?

Air moves from higher pressure → lower pressure.

Alveolar LOW = air IN
Alveolar HIGH = air OUT

What can change alveolar pressure?

Passive forces and active forces.

Is inspiration active or passive?

Always active — it requires muscle contraction.

What happens to the diaphragm during inspiration?

It contracts and flattens, causing the lower ribs to move outward and increasing chest expansion.

Which muscles are active during inspiration?

Diaphragm + external intercostals.

Is expiration active or passive?

Mostly passive, but it can become active during forced exhalation.

Which muscles are used for active/forced expiration?

Internal intercostals + abdominal muscles.

Why can expiration happen passively?

The respiratory system is elastic and naturally wants to return to its resting position after being stretched during inspiration.

What happens during quiet breathing?

Elastic recoil helps the respiratory system return to its resting position, causing air to move out.

What is elastic recoil?

The natural tendency of the respiratory system to return to its resting position.

When is active force added during exhalation?

During speech breathing and active/forced expiration.

What muscles initiate inspiration?

Diaphragm + external intercostal muscles contract.

What happens to alveolar pressure during inspiration?

Alveolar pressure becomes lower than atmospheric pressure → air moves into the lungs.

What happens to O₂ after air enters the lungs?

O₂ moves from the alveoli → capillaries/blood to oxygenate the blood.

What causes the respiratory system to return toward its resting position during expiration?

Elastic recoil (passive force).

What happens to CO₂ during expiration?

CO₂ moves from the blood → alveoli → exhaled into the environment.

What is the overall sequence of breathing?

Muscle contraction → pressure change → air movement → gas exchange → elastic recoil → expiration.

What do respiratory volumes and capacities tell us?

How much air the lungs can move and store.

What can respiratory volumes and capacities indicate?

Pulmonary health and respiratory function.

Why are respiratory volumes and capacities important for speech?

They help explain breath support, loudness, and phrase length.

What can abnormal respiratory volumes and capacities indicate?

Respiratory weakness or neuromuscular problems.

What functions can abnormalities in respiratory volumes/capacities affect?

Speech, voice, and swallowing.

How can respiratory volume/capacity measurements help with therapy?

They can help guide therapy and breath-support exercises.

What is tidal volume (TV)?

The amount of air inhaled or exhaled during a normal, quiet breath.
⭐ ~500 mL

When does tidal volume increase?

During speech.

What is inspiratory reserve volume (IRV)?

The amount of extra air that can be inhaled beyond a normal inspiration.
⭐ ~3,000 mL

When is IRV used?

When taking a deep breath, such as before prolonged speech.

What is expiratory reserve volume (ERV)?

The amount of extra air that can be exhaled beyond a normal expiration.
⭐ ~1,000–2,000 mL