Respiratory System: Lower

Question 1

lower respiratory tract includes…

Answer 1

• larynx
• trachea
• bronchial tree
• lungs

Question 2

larynx characteristics

Answer 2

• voice box
• composed of hyaline cartilage
• connection b/w pharynx + trachea
• only moves air
• inflammation of larynx mucosa = laryngitis
• paired & unpaired cartilage

Question 3

larynx: unpaired cartilage

Answer 3

thyroid:

• made of hyaline cartilage
• anterior wall of larynx
• adam’s apple

cricoid: ring of hyaline cartilage

epiglottis:

• formed from elastic cartilage
• cover + protect glottis during swallowing

Question 4

larynx: paired cartilage

Answer 4

• all 3 made from hyaline cartilage

- arytenoid: attach vocal cords

Question 5

vocal cords

Answer 5

• ligaments composed of elastic fibers
• folds form vocal cords
• true / false

Question 6

vocal cords: false

Answer 6

• from superior fold of membrane (vestibule fold)
• helps hold breath
• closes larynx

Question 7

vocal cords: true

Answer 7

• from inferior folds of mucous membrane
• no blood vessels = pearl white
• produce vibrating sound
• prevents food + liquids from entering trachea
• glottis consists of vocal cords & opening

Question 8

trachea

Answer 8

• located anterior to esophagus
• connects larynx to left + right primary bronchi
• 20 C-shaped pieces of hyaline cartilage
  > open portion faces esophagus allowing for
  expansion
  > C faces anterior portion + protects against
  tracheal collapse
• ciliated, pseudostratified columnar w/ goblet cells for mucus secretion

Question 9

bronchial tree

Answer 9

• stretches from primary bronchi to alveoli ducts

- decreasing amounts of cartilage & increasing smooth muscle from trachea to inner lung

Question 10

bronchial tree: primary bronchi

Answer 10

• right + left w/ incomplete rings of hyaline cartilage

- branch into secondary (lobar) bronchi

Question 11

bronchial tree: secondary bronchi

Answer 11

• plates of hyaline cartilage

- 3 in right lung + 2 in left lung

Question 12

bronchia tree progreession

Answer 12

primary (INC) > secondary (CO) > tertiary (IRR P) > terminal (NA) > respiratory bronchioles (NA) > alveolar ducts (NA)

Question 13

alveoli

Answer 13

• alveoli ducts > alveolar sacs (multiple alveoli)
• sites for gas exchange
• 300 mill. per lung
• increases surface area for gas exchange

Question 14

respiratory epithelium

Answer 14

• primary bronchi: ciliated pseudostratified columnar w/ goblet cells
• large bronchioles: ciliated simple columnar w/ goblet cells
• small bronchioles: ciliated simple cuboidal w/o goblet cells
• terminal bronchioles: non-ciliated simple cuboidal
• alveolar ducts: non-ciliated simple squamous

Question 15

lungs

Answer 15

• right + left are separated by mediastinum
• left lobes: inferior + superior (cardia notch)
• right lobes: superior, middle, inferior
• innervated by nervous system

Question 16

lungs: pleura

Answer 16

• surrounds lungs
• serous membrane = visceral + parietal layer
• pleura cavity: area b/w 2 pleura membranes containing serous fluid (lubricate, reduce friction, holds lungs to wall)

Question 17

respiratory membranes consists of…

Answer 17

1) alveolus wall
2) elastic epithelial basement membrane
3) capillary basement membrane
4) capillary endothelium

Question 18

alveolus wall: type I alveolar cells

Answer 18

• simple squamous epithelium

- site of O2 and CO2 exchange

Question 19

alveolus wall: type II alveolar cells

Answer 19

• simple cuboidal epithelium
• secrete fluid containing surfactant (lipoprotein + phospholipids that reduce surface tension)
• free surface = microvilli > increase surface area

Question 20

alveolus wall: macrophages

Answer 20

• remove dust, pollen, debris from air

- move freely across alveolar surface

Question 21

capillary basement membrane

Answer 21

fused to alveolar basement membrane

Question 22

capillary endothelium

Answer 22

endothelial cells that form simple squamous layer

Question 23

mycobacterium tuberculosis

Answer 23

• caused by tuberculosis
• thickens respiratory membrane
• membrane tissue is replaced with fibrous CT (scar tissue)
• decrease elasticity & capacity for gas exchange

Question 24

ways blood moves to lungs

Answer 24

1) pulmonary circulation
2) systemic circulation
3) bronchial arteries

Question 25

pulmonary circulation

Answer 25

right ventricle > pulmonary arteries > lungs > pulmonary veins > left atrium

Question 26

systemic circulation

Answer 26

L atrium > L ventricle > aorta > bronchial arteries > cells of bronchi + bronchioles (lung) > bronchial veins > superior vena cava > R atrium

Question 27

bronchial arteries

Answer 27

• branch off to descending aorta that gives blood to systemic circulation
• carry oxygenated blood to respiratory tissues

Question 28

bronchial veins

Answer 28

• empties into right atrium

- most blood enters left atrium via pulmonary veins

Question 29

inhalation

Answer 29

regular: diaphragm + intercostal muscle contract
forced: diaphragm, external intercostals, pectoralis minor, scalene + sternocleidomastoid contract

Question 30

exhalation

Answer 30

regular: diaphragm + external intercostal muscles relax
forced: internal intercostals + abdominal muscles contract

Question 31

pulmonary edema

Answer 31

accumulation of fluid in lungs + alveoli

Question 32

pulmonary embolism

Answer 32

• blockage in pulmonary circulatory route
• broken blood clot
• result may be death

Question 33

pneumothorax

Answer 33

• entry of air to pleural cavity

- causes lung to collapse

Question 34

emphysema

Answer 34

• enlargement + destruction of alveolar wall
• due to inability to inhibit proteases in lungs
  > smoking = accumulation of neutrophils (release
  proteases)
  > results in larger alveoli w/ decreased elasticity
  (difficult breathing)