Chapter 9: Respiratory System

Question 1

What system includes the lungs, airways (numerous tubes of various sizes such as pharynx, larynx, trachea, bronchi) and associated structures. They are specialized for gaseous exchange between blood and air, including the uptake of oxygen and the release of carbon dioxide.

Answer 1

respiratory system

Question 2

This mechanism that creates pressure differences that move air into (inspiration) and out of (expiration) the lungs, includes the diaphragm, rib cage, intercostal muscles, abdominal muscles, and elastic connective tissue in the lungs.

Answer 2

Ventilating mechanism

Question 3

What is active, involving muscle contraction. To inhale, the intercostal muscles lift the ribs while the diaphragm and abdominal muscles lower the floor of the thoracic cavity. This enlarges the cavity, creating a vacuum that draws air through the airways. The incoming air expands the airways, inflates the lungs, and stretches the elastic connective tissue.

Answer 3

Inspiration (inhalation)

Question 4

What is more passive: Relaxing the muscles allows the elastic fibers to retract, contracting the lungs and forcing air out.

Answer 4

Expiration (exhalation)

Question 5

This portion includes the nasal cavity, nasopharynx, larynx, trachea, bronchi, bronchioles and the terminal bronchioles. It humidifies, cools or warms, and cleanses the inspired air of particulate matter, infectious microorganisms and other airborne matter.

Answer 5

Conducting portion

Question 6

A blanket which covers the mucosal surface of the conducting airways, serves to trap inhaled particles and convey them and cellular debris out of the system.

Answer 6

mucociliary blanket

Question 7

What rings encircle the lumen of the trachea?

Answer 7

Incomplete hyaline cartilage rings

Question 8

As the trachea divides into bronchi and the bronchi enter the lungs, the hyaline cartilage rings are replaced by?

Answer 8

cartilage plates

Question 9

What cartilage disappear from the conducting passageways when the diameter of the bronchioles is reduced to about 1 mm.?

Answer 9

Cartilage plates

Question 10

The final air passageways of the conducting system are the ?, with diameters ranging from 0.5 mm to 1.0 mm.

Answer 10

terminal bronchioles

Question 11

What is the site of actual exchange of gases and is the distal continuation of the conducting portion?

Answer 11

Respiratory portion

Question 12

The terminal bronchioles of the conducting system give rise to the?

Answer 12

respiratory bronchioles

Question 13

Terminal bronchioles and respiratory bronchioles represent the transitional structures between the conducting and respiratory portions of the respiratory system because the respiratory bronchioles contain thin-walled outpocketings, the?

Answer 13

alveoli

Question 14

What exchange can only occur in the alveoli and blood in the capillaries is very thin?

Answer 14

Respiration or gaseous exchange

Question 15

Thus, the functional units of the lungs are the ?, which occur in clusters at the end of the bronchial tree.

Answer 15

Alveoli

Question 16

the tube-like respiratory tract has layered walls whose lining epithelium is derived from the?

Answer 16

endoderm

Question 17

The epithelium of the extrapulmonary passages (outside of lungs), trachea bronchi, and larger bronchioles are?

Answer 17

ciliated pseudostratified columnar epithelium

Question 18

What type of epithelial cell predominate in the tract. Each has about 300 motile cilia on its apical surface. There are associated basal bodies in the apical cytoplasm.

Answer 18

Ciliated columnar cells

Question 19

What type of epithelial cell are the second most numerous types. They secrete the mucus that covers the epithelium and traps and removes bacteria and other particles from the inspired air. Cilia projecting from the columnar cells sweep the contaminated mucus toward the mouth for disposal.

Answer 19

Mucous goblet cells

Question 20

What type of epithelial cell are also columnar, these cells lack cilia; they often have abundant apical microvilli. Two types are present: one resembles an immature cell and apparently serves to replace dead ciliated or goblet cells; the other has nerve endings on its basal surface and appears to be a sensory receptor.

Answer 20

Brush cells

Question 21

What type of epithelial cell are small round cells that lie on the basal lamina but do not reach the lumen. They appear to be stem cells that can replace the other cell types.

Answer 21

Basal cells

Question 22

What type of epithelial cell resemble basal cells, but they contain many small cytoplasmic granules and exhibit DNES (diffuse neuroendocrine system) activity.

Answer 22

Small granule cells

Question 23

What refers to tissue organization or type undergone by epithelia in response to changes in physical and chemical environment?

Answer 23

Metaplasia

Question 24

What consists of connective tissue and contains mucous glands in the upper tract (from the nasal cavity to the bronchi). Its elastic fiber content increases toward the alveoli. Skeletal connective tissue support begins as cartilage and bone in the nasal cavity and becomes cartilage only in the larynx. It gradually decreases, disappearing at the level of the bronchioles.

Answer 24

LAMINA PROPRIA

Question 25

What muslce begins in the trachea, where it joins the open ends of the C-shaped tracheal cartilage. In the bronchi, many layers of smooth muscle cells encircle the walls in a spiral pattern. From this point, the thickness of the muscle layer gradually decreases until it disappears at the level of the alveolar ducts.

Answer 25

SMOOTH MUSCLE

Question 26

This cavity is divided by the nasal septum into two bilaterally symmetric cavities that open to the exterior through the nares (nostrils). Each cavity consists of two chambers - a vestibule and a nasal fossa that differ in position, size and wall structure.

Answer 26

NASAL CAVITY

Question 27

What region or nasal cavity represents the point of reflection of the skin as the mucous membranes of the nasal cavity. It is lined by non-keratinized stratified squamos epithelium. Pigment cells may be present. The muscularis mucosa is absent. The lamina propria - tunica submucosa is coarse areolar connective tissue that blends with the underlying fascia of muscle or the fibrous layer of the associated investments of bone or cartilage. Hairs (vibrissae), sweat glands, and sebaceous glands occur in the cutaneous part. Branched tubuloalveolar serous and mixed glands may also be present. These glands assist in humidifying inspired air.

Answer 27

Vestibular region

Question 28

Specialization in the nasal vestibule of what animal the rostral portion is lined by an integument containing vibrissae, sebaceous glands and sweat glands. A nasal diverticulum lined with skin is present lateral to the nasal passage and opens into the rostral portion.

Answer 28

Equine

Question 29

Specialization in the nasal vestibule of what animal a second ostium of the nasolacrimal duct is frequently present in the caudo-lateral surface of the ventral conchae?

Answer 29

Dog and pig

Question 30

Specialization in the nasal vestibule of what animal the lateral nasal gland and duct are absent?

Answer 30

Cattle

Question 31

What region of nasal cavity comprises the bulk of the nasal cavity, lined by ciliated pseudostratified columnar epithelium with goblet cells. Muscularis mucosa is absent. The lamina propria-tunica submucosa is areolar connective tissue. Numerous tubule-alveolar mixed glands, the nasal glands that are predominantly serous are scattered throughout this layer. Erectile tissues that consist of cavities lined by endothelium and are continuous with blood vessels may also be present. The glandular tissue humidifies the air while the engorged erectile tissue cools or warms it by using the mucous membranes as a heat transfer device.

Answer 31

Respiratory region

Question 32

What region of nasal cavity is a specialized area for olfaction that is located on the ethmoturbinates, dorsal turbinate and nasal septum. It may be yellow, brown, gray or black in color due to the accumulation of pigment. The lining epithelium is ciliated pseudostratified columnar. It is very thick and may have as many as 15 layers of nuclei.

Answer 32

Olfactory region

Question 33

What type of cell in the olfactory region are tall with broad apices and narrow bases. The nucleus is oval, vesicular and located towards the apex of the cell. Pigment granules may be present. Sustentacular cells are replaced by gland cells. Olfactory gland acini are composed of light serous and dark mucus-secreting cells.

Answer 33

Supportive (sustentacular) cells

Question 34

What type of cell in the olfactory region are cuboidal in shape.

Answer 34

Basal cells

Question 35

What type of cell in the olfactory region are modified neurons, the basal process of which continues to the brain as axons of the first cranial nerve. The nucleus is round, vesicular and located centrally or basally. The apex has a bulbous projection, the olfactory vesicle, from which cilia or olfactory hairs project.

Answer 35

Neurosensory olfactory cells

Question 36

What type of cell in the nonolfactory epithelium are electron dense columnar cells attached at the base of the epithelium to the basal lamina of the hemidesmosomes?

Answer 36

Basal cells

Question 37

What type of cell in the nonolfactory epithelium are anchored to the apical cytoplasm by the basal bodies and the microvilli; sometimes branched, contain microfilaments and extend down into the cytoplasm.

Answer 37

Ciliated cells

Question 38

What type of cell in the nonolfactory epithelium occur either as goblet or as slender mucus-secreting cells, varies with both secretory phase and location within the nasal cavity.

Answer 38

Secretory cells

Question 39

What type of cell in the nonolfactory epithelium have long, thick microvilli containing bundles of microfilaments, and a cytoplasm containing mitochondria, granular ER, and a large number of filaments?

Answer 39

Brush cells

Question 40

What organ is a tubular, blind-ending organ located in the mucosa of the ventral portion of the nasal septum. It consists of an external cartilaginous support, a middle lamina propria that is both highly glandular and vascular, and an internal epithelial duct.

Answer 40

VOMERONASAL ORGAN

Question 41

What cartilage is J-shaped, enclosing all the dorsolateral portion of the vemoronasal organ?

Answer 41

hyaline vomeronasal cartilage

Question 42

What glands secrete into the vomeronasal organ through the commissures between lateral and medial mucosal walls?

Answer 42

Vomeronasal glands

Question 43

What are continuous with the nasal cavity. These are spaces or dilated cavities within the maxillary, frontal, ethmoid and sphenoid around the nose and eyes. The lining epithelium is either cuboidal or squamos to the ciliated pseudostratified columnar type. Goblet cells and mucous glands occur less frequently. Mucus produced here drains into the nasal fossa through small openings protected by conchae. Erectile tissue is absent.

Answer 43

PARANASAL SINUSES

Question 44

What is a broad single cavity overlying the soft palate. It connects the nasal cavity with the laryngopharynx. - Lining epithelium - pseudostratified ciliated columnar epithelium with goblet cells. - Muscularis mucosa is absent. - Lamina propria-tunica submocosa consists of loose connective tissue with numerous diffuse and nodular lymphatic tissue and pharyngeal tonsils. It is infiltrated with lymphocytes and granulocytes. Glands present are branched tubuloalveolar, mucous, serous and mixed glands. - Erectile fibers are prominent. - Tunica muscularis is skeletal muscle in various orientations. - Tunica adventitia is continuous with the underlying fascia.

Answer 44

NASOPHARYNX

Question 45

What is a bilaterally symmetric tube that lies in the neck between the base of the laryngopharynx and the trachea. During swallowing, its opening is protected by the epiglottis. Taste buds may be present in the epiglottis of carnivores, swine, ruminants and man. Its walls are supported by several laryngeal cartilages in the lamina propria, and contain skeletal muscle and house the vocal apparatus. - Lining epithelium - either stratified squamos or pseudostratified ciliated columnar. - Muscularis mucosa is absent. - Lamina propria-tunica submucosa is areolar connective tissue with diffuse and nodular lymphatic tissue and branched tubuloalveolar, mucous, serous and mixed glands. - Tunica muscularis consists of striated muscles containing cartilage - Tunica adventia is typical.

Answer 45

LARYNX

Question 46

This flap of tissue extends toward the oropharynx and the trachea. It is covered on its superior surface by non-keratinized stratified squamos epithelium and on its inferior surface by respiratory epithelium. The lamina propria contains a few mucous glands and a small plate of elastic cartilage.

Answer 46

Epiglottis

Question 47

Several cartilages frame the laryngeal lumen and serve as attachments for the skeletal muscles that control the vocal apparatus. The large thyroid, cricoid and most of the paired arytenoid cartilage are hyaline, while smaller ones - the paired cuneiform and corniculate, the epiglottic and the tips of the arytenoid are elastic.

Answer 47

Laryngeal cartilage

Question 48

The broad part of the larynx, below the epiglottis and surrounded by the thyroid cartilage, contains two bilaterally symmetric pairs of mucosal folds.

Answer 48

Vocal apparatus

Question 49

These are the upper pair of folds in the larynx. They are covered by respiratory epithelium and contain serous glands whose ducts open mainly into the cleft that separates them from the lower pair of the folds.

Answer 49

False vocal cords (vestibular folds)

Question 50

This lower pair of folds is covered by stratified squamos epithelium. Each contains two major structures: a large bundle of elastic fibers that runs front to back called the vocal ligament; and a bundle of skeletal muscle that runs parallel to the ligament called the vocalis muscle.

Answer 50

True vocal cords

Question 51

What provides an air passageway between the larynx and the pulmonary bronchi. It is a semiflexible and semicollapsible tube in the ventral portion of the neck that extends from the larynx to the thoracic cavity. Its most characteristic feature is the presence of C-shaped cartilage rings whose open ends are directed posteriorly. The opening is bridged by a fibroelastic ligament that prevents over distention as well as smooth muscle bundles (trachealis muscle) that constrict the lumen and increase the force of air flow during coughing and forced expiration.

Answer 51

TRACHEA

Question 52

Cell type in the epithelial lining of the trachea that are oriented with long axes parallel to and in contact with the basal lamina. It is believed to be the progenitor cell for the other epithelial cell types.

Answer 52

Basal cells

Question 53

Cell type in the epithelial lining of the trachea have basal, lobulated nuclei and apical microvilli containing abundant granular ER and apical electron dense secretory granules.

Answer 53

Serous cells

Question 54

Cell type in the epithelial lining of the trachea that (bronchiolar exocrine cells) have characteristics of both secretory cells and cells capable of metabolizing xenobiotic compounds.

Answer 54

Clara cells

Question 55

Cell type in the epithelial lining of the trachea that are also known as Kultschitzky-like (K-cells), APUD (amine precursor uptake decarboxylation) cells, are pyramid-shaped with their bases on the basal lamina and contain dense-cored, argyrophilic granules, abundant ER, Golgi complex, ribosomes and many filaments.

Answer 55

Neuroendocrine cells

Question 56

What arise at the bifurcation of the trachea and are structurally similar to it.

Answer 56

extrapulmonary bronchi

Question 57

What are subdivided into: primary, secondary and tertiary bronchi based on their branching, luminal size and mural constituents. The epithelial lining is pseudostratified columnar composed primarily of secretory cells, ciliated cells, and basal cells.

Answer 57

intrapulmonary bronchi

Question 58

There are two primary bronchi, one entering each lung. Their histologic appearance is quite similar to that of the trachea, but their cartilage rings and spiral bands of smooth muscle completely encircle their respective lumens. The path of the right primary bronchus is more vertical than that of the left.

Answer 58

Primary bronchi

Question 59

These lobar bronchi are branches that arise directly from the primary bronchi; each supplies one pulmonary lobe. Their histologic structure is similar to that of the primary bronchi except that their supporting cartilage are arranged as irregular plates, or islands of cartilage rather than “C”- or” U”-shaped rings.

Answer 59

Secondary bronchi

Question 60

Arising directly from the secondary bronchi, which they resemble histologically, each of these segmental bronchi supplies one bronchopulmonary segment (pulmonary lobule). The different number of secondary bronchi causes tertiary branching pattern to differ between the right and left lungs. Except for a decrease in overall diameter, the histologic appearance of tertiary bronchi is identical to that of secondary bronchi.

Answer 60

Tertiary bronchi

Question 61

What is considered as a compound tubuloalveolar gland. Its excretory product, carbon dioxide is secreted across the alveolar surface in exchange to the uptake of oxygen. It has an extensive amount of elastic fibers that account for part of its contractility in response to an alteration in the size of the thoracic cavity.

Answer 61

lung

Question 62

Each lung is divided into ?, the number of which is species variable.

Answer 62

lobes

Question 63

Each lobe is divided into ? These are structural unit rather than a functional unit. It comprises a cluster of acini that is separated from the adjacent clusters by connective tissue septa.

Answer 63

lobules

Question 64

What are the smallest division and the most distal of the nonrespiratory or conductive portions of the lung. - Lining epithelium is simple columnar or simple cuboidal cells and is devoid of goblet cells. The lining cells are ciliated at the primary bronchioles. Cilia extend further down the respiratory tree than do the glands. - Lamina propria is fine collagenous and elastic fibers. - Muscularis mucosa is present and continuous. - Cartilage is absent.

Answer 64

Bronchioles

Question 65

What bronchioles are the most distal conducting airway free of alveoli. They are the primary conducting supply to the secondary lobule and divide into several respiratory bronchioles. They are the smallest components of the conducting portion of the respiratory system lined by simple columnar or cuboidal epithelium composed of ciliated and clara cells and have no goblet cells.

Answer 65

Terminal (or tertiary) bronchioles

Question 66

What bronchioles are the initial part of the respiratory portion responsible for the exchange of gases, with a simple cuboidal lining which resembles that of the terminal bronchioles but which is interrupted by thin-walled saccular evaginations called alveoli. The number of alveoli increases as the respiratory bronchioles proceed distally. As the alveoli increase in number, the cilia decrease until they disappear. Goblet cells are absent. The lamina propria is indistinct. The muscularis mucosa is present but loosely arranged.

Answer 66

Respiratory bronchioles

Question 67

What is the respiratory area of the lungs where exchange of gases takes place. It consists of alveolar ducts, alveolar sacs, alveoli and air spaces contained within these structures.

Answer 67

Parenchyma

Question 68

What are the distal extensions of the respiratory bronchioles where the alveoli are so dense that the wall consists almost entirely of these sacs and the lining has been reduced to small knobs of smooth muscle covered cilia-free simple cuboidal cells. They divide and expand peripherally into alveolar sacs or saccules that are completely lined by alveoli. The common opening of the sacs is called atria.

Answer 68

Alveolar ducts

Question 69

What are the distal termination of alveolar ducts. The arrangement is comparable to a long hallway (alveolar duct) leading to a rounded foyer (atrium). The foyer has small doorways leading to some small rooms (alveoli), but also has two or more larger doorways leading into short, dead-end hallways (alveolar sacs). The short hallways are also lined by small rooms (alveoli).

Answer 69

Atria and alveolar sacs

Question 70

What occur only in the respiratory portion. These small sacs open into a respiratory bronchiole, an alveolar duct, an atrium, or an alveolar sac.

Answer 70

Alveoli

Question 71

Alveoli are separated by thin walls termed?

Answer 71

interalveolar (or alveolar) septa

Question 72

What are critical to respiratory function since they specialize for gas exchange. It consist of two simple squamos epithelial layers with the interstitium sandwiched between them. The interstitium consists of continuous (nonfenestrated) capillaries embedded in an elastic connective tissue that includes elastic and collagen fibers, ground substance, fibroblast, mast cells, macrophages, leukocytes, and contractile interstitial cells that contract in response to epinephrine and histamine. This elastic tissue is an important component in ventilating mechanism.

Answer 72

Interalveolar septa

Question 73

Whatis the functional unit of the gas exchange area. It includes all of those airspaces distal to one terminal bronchiole

Answer 73

Acinus or terminal respiratory unit

Question 74

Types of cell in the alveoli that is the most abundant, are squamous alveolar cells that line all of the alveolar surfaces.

Answer 74

Type I pneumocytes or membranous pneumocytes

Question 75

Types of cell in the alveoli that are great alveolar cells interspersed among the squamous alveolar cells either singly or in small groups. These cells are secretory in nature; they synthesize and secrete a phospholipid-rich product called pulmonary surfactant. As surfactant is released from type II cells, it spreads over the alveolar cell surfaces, moistens them, and lowers the surface tension in the alveoli. By decreasing surface tension in the alveoli surfactant stabilizes alveolar diameters and prevents their collapse during respiration by reducing collapsing forces to a minimum.

Answer 75

Type II pneumocytes or granular pneumocytes

Question 76

Type II pneumocytes or granular pneumocytes synthesize and secrete a phospholipid-rich product called ? As it is released from type II cells, it spreads over the alveolar cell surfaces, moistens them, and lowers the surface tension in the alveoli. By decreasing surface tension in the alveoli surfactant stabilizes alveolar diameters and prevents their collapse during respiration by reducing collapsing forces to a minimum.

Answer 76

pulmonary surfactant

Question 77

Types of cell in the alveoli that are derived from the circulating blood monocytes that originate in the bone marrow. They are found in the connective tissue of alveolar septa and on the surface of the alveoli. The primary function of the this cell is protection; they clean the alveoli of invading microorganism and inhaled particulate matter. They also phagocytose blood cells that enter the alveoli as a result of heart failure and are thus designated as heart failure cells.

Answer 77

Alveolar macrophages, or dust cells

Question 78

This term refers to the structures that oxygen and CO2 must cross to be exchanged. It includes the following layers: 1. The film of pulmonary surfactant on the alveolar surface 2. The cytoplasm of the squamos epithelial cells (type I cells) 3. The fused basal lamina sandwiched between type I alveolar and capillary endothelial cells. 4. The cytoplasm of the endothelial cells lining the interstitial capillaries.

Answer 78

Blood-air barrier

Question 79

have two layers: one covering the lungs and the other covers the internal wall of the thoracic cavity.

Answer 79

PLEURA

Question 80

What pleura completely cover both the lungs except at the hilum and the pulmonary ligament. The pleura is a serous membrane consisting of mesothelial cells that vary from squamos to cuboidal and a layer of varying amounts of dense irregular connective tissue and elastic fibers.

Answer 80

visceral or pulmonary pleura

Question 81

Bordered by the mesothelial cells, the narrow ? lies between the parietal and visceral pleurae

Answer 81

pleural cavity