Biology Chapter 13: The Respiratory System

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Questions and Answers

Which of the main bronchi is larger in diameter?

right

Which of the main bronchi is more horizontal?

left

Which main bronchi is the most common site for lodging of a foreign object that has entered the respiratory passageways?

right

Air enters the nasal cavity of the respiratory system through the (1).

nostrils (nares) Signup and view all the answers

The nasal cavity is divided by the midline (2).

nasal septum Signup and view all the answers

Mucous membrane-lined cavities called (6) are found in several bones surrounding the nasal cavities.

paranasal sinuses Signup and view all the answers

The passageway common to the digestive and respiratory systems, the (8), is often referred to as the throat.

pharynx Signup and view all the answers

Clusters of lymphatic tissue, (10), are part of the defensive system of the body.

tonsils Signup and view all the answers

Reinforcement of the trachea with (11) rings prevents its collapse during (12) changes that occur during breathing.

cartilage, pressure Signup and view all the answers

The largest cartilage in the larynx is the (14) cartilage.

thyroid Signup and view all the answers

Within the larynx are the (15), which vibrate with exhaled air.

vocal cords Signup and view all the answers

With the exception of the stroma of lungs, which is (1) tissue, the lungs are mostly air spaces.

elastic connective Signup and view all the answers

What are the three functions of the larynx?

<ol> <li>Provide open airway 2. Switching mechanism for food and air 3. Voice production</li> </ol> Signup and view all the answers

What type of cartilage forms the epiglottis?

elastic cartilage Signup and view all the answers

What important role is played by the cartilage rings that reinforce the trachea?

Prevents airways from collapsing during changes during breathing. Signup and view all the answers

What occurs when the trachealis muscle contracts?

Contraction reduces the diameter of the trachea. Signup and view all the answers

In healthy lungs, what is always lower than atmospheric pressure?

Intrapleural pressure Signup and view all the answers

What is the common name for the thyroid cartilage?

Adam's apple Signup and view all the answers

What is the respiratory rate of a newborn baby?

40 to 80 respirations per minute Signup and view all the answers

What is the total amount of exchangeable air called?

vital capacity Signup and view all the answers

What condition is characterized by a lack of cessation of breathing?

Apnea Signup and view all the answers

What is chronic bronchitis?

Condition characterized by increased mucus production, which clogs respiratory passageways and promotes coughing. Signup and view all the answers

What is asthma?

Respiratory passageways narrowed by bronchiolar spasms. Signup and view all the answers

What is emphysema?

Condition characterized by loss of lung elasticity and an increase in size of the alveolar chambers. Signup and view all the answers

What is dyspnea?

Difficulty breathing Signup and view all the answers

Study Notes

Anatomy of the Respiratory System

Right main bronchus is larger in diameter and is the most common site for fluid obstruction.
Left main bronchus is more horizontal in orientation.

Nasal Cavity Functions

Air enters via nostrils (nares) and is divided by the nasal septum.
Mucosa in the nasal cavity warms, moistens, and cleanses incoming air.
Paranasal sinuses lighten the skull and resonate sound.
The pharynx connects the nasal cavity to the larynx.

Trachea and Larynx

Trachea is reinforced with C-shaped cartilage rings to prevent collapse during pressure changes.
Epiglottis closes the larynx during swallowing, preventing food from entering airways.
The thyroid cartilage is the largest laryngeal cartilage, commonly known as the Adam's apple.
Vocal cords within the larynx vibrate to enable sound production.

Gas Exchange Structures

Alveoli are the primary sites for gas exchange; their walls are primarily composed of squamous epithelial cells.
Surfactant produced by cuboidal cells reduces surface tension in alveoli.

Respiratory Pressures

Intrapleural pressure remains lower than atmospheric pressure to keep lungs inflated.
Intrapulmonary pressure (intra-alveolar pressure) changes during breathing; decreases during inspiration and rises during forced expiration.
Equalization of intrapleural pressure with atmospheric pressure leads to lung collapse.

Respiratory Processes

Inspiration is the inhalation phase; expiration is exhalation.
Internal respiration involves gas exchange between systemic capillary blood and body cells.
External respiration occurs between alveolar air and pulmonary capillary blood.

Respiratory Zones

Conducting zone includes structures like the nose, pharynx, larynx, trachea, bronchi, and bronchioles.
Respiratory zone comprises bronchioles, alveolar ducts, alveolar sacs, and alveoli.

Respiratory Conditions

Emphysema: loss of lung elasticity and enlarged alveolar chambers.
Chronic bronchitis: increased mucus obstructs airways.
Asthma: bronchiolar spasms lead to narrowed airways.
Tuberculosis: serious infection spread via airborne bacteria.
Hypoxia: oxygen deficiency, often chronic.
Infant respiratory distress syndrome: associated with inadequate surfactant in underdeveloped lungs.

Respiratory Volumes

Tidal volume represents the air volume inhaled or exhaled during normal breathing.
Vital capacity is the total amount of exchangeable air within the lungs.
Residual volume allows continuous gas exchange.

Aging leads to decreased lung elasticity and capacity, making older adults more susceptible to respiratory infections.

Respiratory Reflexes

Coughing clears lower airways; sneezing clears upper airways.
Hiccups are sudden inspirations caused by diaphragm spasms.
Yawning ventilates all alveoli, providing a deep breath.

Respiratory Rate

Newborns have a respiratory rate of approximately 40 to 80 breaths per minute.
Healthy adults typically have a respiratory rate of 12 to 18 breaths per minute.

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Description

Test your knowledge on Chapter 13 of Biology, focusing on the respiratory system. This quiz includes important concepts about the bronchi and their characteristics. Enhance your understanding of how air travels through the respiratory passageways.