Week Three: Respiratory System

Question 1

What is the primary function of the respiratory system?

Answer 1

Bring oxygen into the body and carbon dioxide out of it

Question 2

What are the secondary functions of the respiratory system?

Answer 2

Voice production (phonation)
Regulation of body temperature
Regulation of acid base balance (O2/CO2)
Sense of smell

Question 3

What is external respiration?

Answer 3

Exchange of oxygen and carbon dioxide between the inhaled air and the blood flowing through the pulmonary capillaries

Question 4

What is internal respiration?

Answer 4

Exchange of oxygen and carbon dioxide between the blood in the systemic capillaries and all the cells and tissues of the body

Question 5

Structures of the upper respiratory system include…

Answer 5

Nostrils
Nasal passages
Pharynx
Larynx
Trachea

Question 6

What are the nares (nostrils)

Answer 6

External openings of the respiratory tube that lead into the nasal passages

Question 7

What are nasal passages?

Answer 7

Between the nostrils and the pharynx

Question 8

What is the nasal septum?

Answer 8

Separates the left and right nasal passage

Question 9

What are the hard and soft palates?

Answer 9

Separate the nasal passages from the mouth

Question 10

What are turbinates (nasal conchae)

Answer 10

Divide each nasal passage into three main passageways

Thin, scroll-like bones covered with nasal epithelium

Question 11

What are nasal passages lined with?

Answer 11

Pseudostratified columnar epithelium

Question 12

What is mucus in the nose secreted by?

Answer 12

Mucus glands and goblet cells

Question 13

What are the functions of the nasal passages?

Answer 13

Warm, humidify, and filter inhaled air

Question 14

What are paranasal sinuses?

Answer 14

Cillated outpouchings of the nasal passages contained within spaces in certain skull bones
(Secrete mucus)
Most animals have two frontal sinuses and two maxillary sinuses

Question 15

What is the pharynx?

Answer 15

Common passageway for respiratory and digestive system

Question 16

Why is the soft palate important for the pharynx?

Answer 16

Soft palate divides pharynx into the dorsal nasopharynx (respiratory passageway) and the ventral oropharynx (digestive passageway)

Question 17

What happens when you swallow?

Answer 17

Breathing stops, opening into larynx is covered, material to be swalled moves to rear of pharynx and breathing resumes

Question 18

What is the larynx?

Answer 18

Short, irregular tube connecting pharynx with the trachea

Composed of segments of cartilage that connect to each other and surrounding tissues by muscles

Question 19

What holds the larynx in place?

Answer 19

Hyoid bone

Question 20

What is the epiglottis?

Answer 20

Leaf shaped and projects forward from the ventral portion of the larynx
(during swallowing it is pulled back to cover the opening of the larynx)

Question 21

What are arytenoid cartilages?

Answer 21

Attachment is the site of vocal cords

Question 22

What forms the boundaries of the glottis?

Answer 22

Arytenoid cartilages and vocal cords

Question 23

What are vocal cords?

Answer 23

Two connective tissue bands attached to the arytenoid cartilages
Stretched across lumen of larynx parallel to each other
Vibrate as air passes over them

Question 24

What controls the tension of vocal cords?

Answer 24

Muscles attached to the arytenoid cartilages:
Complete relaxtion opens the glottis wide: no sound
Lessening the tension produces lower-pitched sounds
Tightening the tension produced higher-pitched sounds

Question 25

What is the function of the larynx?

Answer 25

Prevention of foreign material being inhaled | Controls airflow to and from the lungs

Question 26

Where is the trachea located?

Answer 26

Extends from larynx into thorax | Divides into two main bronchi that enter the lungs

Question 27

Structures of the lower respiratory tract include...

Answer 27

Bronchi Bronchioles Alveolar ducts Alveoli

Question 28

Describe the bronchial tree

Answer 28

Each bronchus divides into smaller bronchi, which divide into smaller bronchi, and then tiny bronchioles Bronchioles subdivide into alveolar ducts Alveolar ducts end in groups of alveoli which are arranged like bunches of grapes

Question 29

What are alveolar sacs?

Answer 29

Groups of alveoli

Question 30

What is bronchodilation?

Answer 30

Bronchial smooth muscle relaxes (aids respiratory effort during intense physical activity)

Question 31

What is bronchoconstriction?

Answer 31

Bronchial smooth muscle partially contracts | Reduces size of air passage

Question 32

What is alveoli?

Answer 32

Site of external respiration Tiny, thin walled sacs of simple squamous epithelium Surrounded by networks of capillaries Lined with fluid that contains surfactant (net surrounding ball)

Question 33

What is hilus?

Answer 33

Small, well defined area on medial side of lung Site where air, blood, lymph, and nerves enter and leave the lung (attaches at bronchi)

Question 34

Where does deoxygenated blood enter the lungs?

Answer 34

From right ventricle of heart through the pulmonary artery

Question 35

Where does oxygenated return to the heart?

Answer 35

Left side of heart

Question 36

What is the mediastinum?

Answer 36

Area between lungs Contains heart, trachea, esophagus, blood vessels, nerves, lymphatic structures Divides throacid cavity in two parts

Question 37

What is the pleura?

Answer 37

Thin membrane that lines thoracic cavity and covers organs and structures in the thorax

Question 38

The visceral layer of pleura is where?

Answer 38

Covers thoracic organs and structures

Question 39

Parietal layer of pleura is where?

Answer 39

Lines the cavity

Question 40

What is the diaphragm?

Answer 40

Thin, dome shaped skeletal muscle sheet Forms caudal boundary of thorax Flattens when it contracts, enlarges volume of thorax and aids inspiration

Question 41

What is inspiration?

Answer 41

Process of drawing air into lungs (inhalation) | Results from enlargement of volume of thoracic cavity by inspiratory muscles

Question 42

What are the main inspiratory muscles?

Answer 42

Diaphragm and external intercostal muscles

Question 43

What is expiration?

Answer 43

Process of pushing air out of the lungs (exhalation)

Question 44

What are the main expiratory muscles?

Answer 44

Internal intercostal muscles and abdominal muscles

Question 45

What is tidal volume?

Answer 45

Volume of air inspired and expired during one breath

Question 46

What is minute volume?

Answer 46

Volume of air inspired and expired during one minute of breathing

Question 47

What is residual volume?

Answer 47

Volume of air remaining in lungs after maximum expiration

Question 48

Describe alveolar gas exchange

Answer 48

Simple diffusion of gas molecules according to concentration gradient O2 diffuses from alveolar air into the blood of alveolar capillary CO2 diffuses from blood into alveolus

Question 49

What controls respiratory muscle contractions?

Answer 49

Medulla oblongata of the brain stem | This directs timing and strength of contractions

Question 50

What are individual control centers?

Answer 50

Inspiration, expiration, breath holding | Can be consciously controlled for brief periods

Question 51

What sets limits on routing resting inspiration and expiration in the lungs?

Answer 51

Stretch receptors

Question 52

What do chemical receptors in the carotid artery and aorta do?

Answer 52

Monitor blood CO2, pH, and O2

Question 53

Increased CO2 in blood and _______ blood pH triggers respiratory center to increase rate and depth of respiration

Answer 53

Decreased

Question 54

Decreased CO2 in blood _________ blood pH, which triggers respiratory center to decrease rate and depth of respiration

Answer 54

Increased

Question 55

What is hypoxia?

Answer 55

Decrease in blood O2 level

Question 56

What is severe hypoxia?

Answer 56

neurons of respiratory center can become so depressed that adequate nerve impulses cannot be sent to the respiratory muscles Can cause breathing to decrease of stop completely