Lecture 11: Respiration

Question 1

What is the purpose of the conduction portion of the respiratory system and what does this include?

Answer 1

Transports air.
Includes: nose, nasal cavity, pharynx, larynx, trachea, and progressively smaller airways, front he primary bronchi to the bronchioles

Question 2

What is the purpose of the respiratory portion of the respiratory system and what does this include?

Answer 2

Carries out gas exchange.

Includes: small airways called respiratory bronchioles and alveolar ducts as well as air sacs called alveoli

Question 3

What are the 4 paranasal sinuses?

Answer 3

Frontal, ethmoidal, sphenoidal, maxillary

Question 4

What covers the paranasal sinuses?

Answer 4

Covered with the same pseudostratified cilliated columnar epithelium as the nasal cavity

Question 5

How does the humidity and temperature change as air enters the respiratory tract and moves into the lungs? As it leaves?

Answer 5

Enters at 25 degrees Celsius and 30% humidity, by the time it reaches lungs it is 37 degrees and 100% humidity. When it exits it is 32 degrees Celsius and 100% humidity

Question 6

What are the 3 thoughts as to why the Neanderthal face pneumatized?

Answer 6

1. Cool body?
2. Warm incoming air?
3. Simply due to a large face?

Question 7

What is the pharynx commonly called?

Answer 7

The throat

Question 8

Where does the pharynx originate and extend?

Answer 8

Originates posterior to the nasal and oral cavities and extends inferiority near the level of the bifurcation of the larynx and esophagus

Question 9

What are the walls of the pharynx lined with and what is characteristic of them?

Answer 9

Lined by a mucosa and contain skeletal muscles that are primarily used for swallowing. Flexible lateral walls are distensible in order to force swallowed food into the esophagus.

Question 10

The pharynx is partitioned into 3 adjoining regions. What are these regions?

Answer 10

• Nasopharynx
• Oropharynx
• Laryngopharynx

Question 11

What is the superiormost region of the pharynx? Where specifically is this found?

Answer 11

Nasopharynx. Located directly posterior to the nasal cavity and superior to the soft palate, which separates it from the posterior part of the oral cavity

Question 12

What typically passes through the nasopharyngeal?

Answer 12

Only air

Question 13

What typically blocks material form the oral cavity and the oropharynx?

Answer 13

The soft palate

Question 14

What is found in the lateral walls of the nasopharynx that connects it to the middle ear?

Answer 14

Auditory tubes

Question 15

What does the posterior nasopharynx wall house?

Answer 15

A single pharyngeal tonsil commonly called the adenoids

Question 16

What is the middle pharyngeal region known as and where is this found?

Answer 16

Oropharynx and is immediately posterior to the oral cavity

Question 17

What binds the oropharynx superiorly and inferiority?

Answer 17

The edge of the soft palate superiorly and the hyoid bone inferiority

Question 18

What typically passes through the oropharynx?

Answer 18

It’s a common respiratory and digestive pathway through which both air and swallowed food and drink pass

Question 19

What forms the entrance to the oropharynx from the oral cavity?

Answer 19

2 pairs of muscular arches, the anterior palatoglossal arches and the posterior palatopharyngeal arches

Question 20

What provides the “first line of defense” against ingested or inhaled foreign materials?

Answer 20

The lymphatic organs of the oropharynx

Question 21

What types of tonsils are found in the oropharynx and where are these located specifically?

Answer 21

Palatine tonsils are on the lateral wall between the arches and the lingual tonsils are at the base of the tongue

Question 22

What is the inferior, narrowed region of the pharynx? Where does this extend and what is it continuous with?

Answer 22

Laryngopharynx. Extends inferiority from the hyoid bone and is continuous with the larynx and esophagus

Question 23

Where does the laryngopharynx terminate at and what is it equivalent to in the larynx?

Answer 23

Terminates at the superior border of the esophagus and is equivalent to the inferior border of the cricoid cartilage in the larynx.

Question 24

What forms the anterior wall of the laryngopharynx?

Answer 24

The larynx (voice box)

Question 25

What is the laryngopharynx lined with? What does it permit the passage of?

Answer 25

Lined with nonkeratinized stratified squamous epithelium and permits passage of both food and air

Question 26

What is the larynx specifically?

Answer 26

Voice box is a short, somewhat cylindrical airway bounded posteriorly by the laryngopharynx and inferiority by the trachea

Question 27

What does the larynx prevent?

Answer 27

Swallowed materials from entering the lower respiratory tract

Question 28

What does the larynx conduct and produce?

Answer 28

Conducts air into the lower respiratory tract and produces sound

Question 29

What is the larynx supported by?

Answer 29

A framework of nine pieces of cartilage (three individual pieces and three cartilage pairs) that are held in place by ligaments and muscles

Question 30

What are the vocal ligaments and what are these called?

Answer 30

Inferior ligaments covered by a mucous membrane called the vocal folds. They are "true vocal cords" because they produce sound when air passes between them

Question 31

What are the vestibular ligaments and what are these called?

Answer 31

Superior ligaments involved in sound production, covered with mucosa and are called the vestibular folds. These are "false vocal cords" because they have no function in sound production but protect the vocal folds

Question 32

What do the vestibular folds attach to?

Answer 32

Corniculate cartilages

Question 33

What determines the quality of sound production?

Answer 33

The tension, length and position of the vocal folds

Question 34

What is the trachea?

Answer 34

A flexible, slightly rigid tubular organ often referred to as the "windpipe"

Question 35

Where does the tranchea extend through and where does this lie?

Answer 35

Extends through the mediastinum and lies immediately anterior to the esophagus, inferior to the larynx and superior to the primary bronchi of the lungs

Question 36

What supports the lateral walls of the trachea?

Answer 36

15-20 C-shaped tracheal cartilages. Cartilage rings reinforce and provide some rigidity to the tracheal wall to ensure that the trachea remains open (patent) at all times. Cartilage rings are connected by elastic sheets called anular ligaments

Question 37

What happens to the trachea at the level of the eternal angle?

Answer 37

It bifurcated into two smaller tubes called the right and left primary bronchi

Question 38

What does the most inferior tracheal cartilage do and form?

Answer 38

Separates the primary bronchi at their origin and forms an internal ridge called the carina

Question 39

What is the bronchial tree?

Answer 39

A highly branched system of air conducting passages that originate from the left and right primary bronchi. Progressively branch into narrower tubes are they diverge throughout the lungs before terminating in terminal bronchioles

Question 40

What is characteristic of the hyaline cartilage that supports the walls of the primary bronchi to ensure that they remain open?

Answer 40

They are incomplete rings

Question 41

How do the right and left primary bronchi vary?

Answer 41

Right is shorter, wider, and more vertically oriented than the left primary bronchi

Question 42

What enters the hilum of each lung together with the primary bronchi?

Answer 42

The pulmonary vessels, lymphatic vessels and nerves

Question 43

What does each primary bronchus branch into?

Answer 43

Several secondary bronchi or lobar bronchi

Question 44

How many secondary bronchi do each lobe have and why?

Answer 44

The left lung has 2 secondary bronchi since it has 2 lobes. | The right lung has 3 secondary bronchi since it has 3 lobes

Question 45

What do the secondary bronchi divide into and how many in each lung?

Answer 45

Tertiary bronch. The right is supplied by 10 tertiary bronchi and the left lung is supplied by 8-10 tertiary bronchi

Question 46

What is each tertiary bronchi called and why?

Answer 46

A segmental bronchus because it supplies a part of the lung called a bronchopulmonary segment

Question 47

The primary bronchus on the right side is straighter inferiorly arising off of the trachea. What is the clinical relevance of this?

Answer 47

If you inhale something, probability is greater on the right hand side

Question 48

Respiratory bronchioles lead to alveolar ducts which contain small saccular outpocketings called ___________. What is the specific function of these outpocketings?

Answer 48

Alveoli Thin wall is specialized to promote diffusion of gases between alveolus and blood in pulmonary capillaries. Contributes to the spongy nature of the lungs

Question 49

Describe asthma in terms of sympathetic/parasympathetic responses in the lungs

Answer 49

When you have asthma, there is more mucous production in the layers of the bronchioles. You also get contraction of the smooth muscle surrounding the bronchioles (Parasympathetic response) Use of an inhaler regulates dilation via sympathetic nervous system - relaxes muscles and allows bronchioles to open up again

Question 50

What are the functions of alveolar type II cells (septal cells)?

Answer 50

Secrete surfactant | Inhibit collapse of alveolus

Question 51

What is the function of alveolar type I cells (squamous alveolar cells)

Answer 51

Promote rapid gas exchange

Question 52

Each lung has a _______ shape. Its wide, concave base rests upon the ___________. Its relatively blunt superior region, called the ______, projects superiorly to a point that is slightly superior and posterior to the clavicle. Toward the midline, the lungs are separated from each other by the ______________. The relatively broad, rounded surface in contact with the thoracic wall is called the _________ surface of the lung.

Answer 52

``` Conical Diaphragm Apex Mediastinum Costal ```

Question 53

Describe the general anatomy of the right lung

Answer 53

``` 3 lobes (superior, middle, inferior) Diaphragmatic recess = potential space so that diaphragm can extend up during exhalation ```

Question 54

Describe the general anatomy of the left lung

Answer 54

``` 2 lobes (superior, inferior) Cardiac notch ```

Question 55

What portion of the lungs contains the pulmonary arteries, primary bronchi, and pulmonary veins?

Answer 55

Hilum

Question 56

What is unique about blood flow in the lungs?

Answer 56

Arteries are carrying deoxygenated blood Veins are carrying oxygenated blood Because veins are carrying the oxygenated blood TO the heart so that it can be pumped through the rest of the body

Question 57

The outer surface of each lung and the adjacent internal thoracic wall are lined by a serous membrane called _________ which is formed from simple squamous epithelium

Answer 57

Pleura

Question 58

Differentiate between the visceral and parietal pleura

Answer 58

Visceral pleura = tightly covers outer surface of each lung Parietal pleura = lines internal thoracic walls, lateral surfaces of mediastinum, and superior surface of diaphragm

Question 59

The parietal and visceral pleural layers are continuous at the ______ of each lung. Between the two layers is fluid called ____________ which is secreted by ____________ membrane

Answer 59

Hilum Surfactant Serous

Question 60

What are the functions of surfactant in the pleural cavity?

Answer 60

Acts as a lubricant - ensuring minimal friction during breathing Creates surface tension for close apposition of lung surfaces with the chest wall = optimal inflation of alveoli during respiration

Question 61

What is a pneumothorax?

Answer 61

The two layers of pleura become unadhered and air enters the pleural cavity

Question 62

What is hemothorax?

Answer 62

Two layers of pleura are separated and blood enters that space - lung collapses

Question 63

What is the function of the lymph nodes/vessels within the connective tissue of the lung as well as around bronchi and pleura?

Answer 63

LNs collect carbon, dust particles, and pollutants that were not filtered out by pseudostratified ciliated columnar epithelium

Question 64

What respiratory muscles help increase thoracic cavity dimensions by elevating the first and second ribs during forced inhalation?

Answer 64

Scalenes

Question 65

What respiratory muscles elevate the ribs when they contract, thereby increasing the transverse dimensions of the thoracic cavity during inhalation?

Answer 65

External intercostals

Question 66

What respiratory muscles depress the ribs when they contract, but only during forced exhalation?

Answer 66

Internal intercostals

Question 67

What small muscle extends across the inner surface of the thoracic cage and attaches to ribs 2-6? It helps depress the ribs

Answer 67

Transversus thoracis

Question 68

What respiratory muscle elevates ribs 2-5 during inhalation?

Answer 68

Serratus posterior superior

Question 69

What respiratory muscle depresses ribs 8-12 during exhalation?

Answer 69

Serratus posterior inferior

Question 70

What 3 muscles help with forced inhalation?

Answer 70

Pectoralis minor Serratus anterior Sternocleidomastoid

Question 71

What general muscles assist in active exhalation?

Answer 71

Abdominal muscles | Includes external/internal obliques, transversus abdominis, and rectus abdominis

Question 72

What is Boyle's Law?

Answer 72

The pressure of a gas decreases if the volume of the container increases, and vice versa (Aka pressure and volume have inverse relationship)

Question 73

Based on Boyle's law, what happens when the volume of the thoracic cavity increases even slightly?

Answer 73

The intrapulmonary pressure decreases slightly, and air flows into the lungs through conducting airways Air flows into lungs from region of higher pressure (atmosphere) to lower pressure (intrapulmonary region)

Question 74

Based on Boyle's law, what happens when the volume of the thoracic cavity decreases?

Answer 74

The intrapulmonary pressure increases and forces air out of the lungs into the atmosphere

Question 75

The trachea, bronchial tree, and lungs are innervated by what nervous system?

Answer 75

Autonomic

Question 76

The involuntary, rhythmic activities that deliver and remove respiratory gases are regulated in what part of the brain?

Answer 76

Brainstem Regulatory respiratory centers are located within the reticular formation through both the medulla oblongata and pons

Question 77

What is the function of the pneumotaxic center in the brainstem?

Answer 77

Inhibits activity of the dorsal respiratory group (DRG)

Question 78

What is the function of the apneustic center in the brainstem?

Answer 78

Stimulates inspiration via the dorsal respiratory group (DRG)

Question 79

What are the effects of aging on the respiratory system?

Answer 79

Less efficient d/t structural changes Decrease in elasticity of CT in lungs reduces gas exchange Decrease in ventilation rate Emphysema may cause loss of alveoli Carbon/dust/pollution accumulate in LNs and lungs

Question 80

What was the function of gills derived from pharyngeal slits in early chordates? How did they breath?

Answer 80

Filter feeding Gas exchange was through the skin

Question 81

What was the problem with respiration through the skin as evolution began to occur?

Answer 81

With an increase in size, surface area was not equivalent to volume of inspiration through skin, needed to change body shape to decrease surface area relative to volume

Question 82

Deep respiration is coupled with locomotion in most vertebrates - what does this mean for them and how has this changed in humans?

Answer 82

Lizards run for short bursts, then have to stop to breathe because respiration is completely coupled with locomotion Humans have decoupled and enhanced respiratory control to permit things like speech while we are in motion

Question 83

What specific anatomical change contributed to the evolution of human speech in terms of enhanced breathing control?

Answer 83

Expanded thoracic vertebral canal demonstrating an increase in thoracic innervation to muscles like intercostals and abdominal muscles