Bio 431 Exam 3 Questions with
Correct Answers
describe the major features of the respiratory mucosa - ANSWER--mucous
membrane
-epithelium and lamina propia
-mucus
- goblet cells
- glands in connective tissue
-may have cilia
-epithelium - variable
list the paranasal sinuses - ANSWER-frontal, ethmoidal air cells, sphenoidal,
maxillary
auditory tubes of the nasopharynx - ANSWER-eustachian, pharyngotympanic
which vocal cords are inelastic? - ANSWER-vestibular folds
which vocal cords are elastic? - ANSWER-vocal folds
vocal cords: sound production - ANSWER-via vocal fold vibrations
cartilage in the larynx - ANSWER-epiglottis: elastic cartilage
thyroid + cricoid: hyaline cartilage
what alters the diameter of the trachea? - ANSWER-ANS, controls the trachealis
smooth muscle
where do the primary bronchi enter the lung? - ANSWER-hilum
also where blood vessels, lymphatic vessels, nerves and bronchi enter the lung
describe the lungs - ANSWER-R: 3 lobes
L: 2 lobes
- divided by fissures (R: horizontal and oblique, L: oblique)
- air filled spaces surrounded by elastic tissue
- enclosed in pleural cavity filled with small amount of fluid which decreases friction
describe the functional importance of the lung being divided into bronchopulmonary
segments - ANSWER-each bronchopulmonary segment has its own air supply,
blood supply, and lymphatic vessels, surrounded by connective tissue
describe the anatomical changes that occur along the branching of the respiratory
structures - ANSWER--smooth muscle increases
-cartilage decreases: C-shaped rings to plates
,-smaller diameter
-thinner epithelium
tissue of the bronchioles - ANSWER-simple cuboidal epithelium
smooth muscle controlled by ANS
sparse to no cilia
respiratory pathway through alveoli - ANSWER-terminal bronchiole -> respiratory
bronchioles -> alveolar duct -> alveolar sacs of many alveoli
explain the functional importance of decreasing surface tension in the alveoli -
ANSWER-keeps alveoli from collapsing, makes them easier to inflate
alveolar cells - ANSWER-macrophages
alveolar type 1: simple squamous epithelial cells, alveolar pores (equalize pressure
between alveoli)
alveolar type 2: epithelial cells that secrete surfactant, decrease surface tension to
keep alveoli from collapsing making them easier to inflate
visceral pleura - ANSWER-membrane on outside of lung
produces serous fluid
parietal pleura - ANSWER-lines wall of thoracic cavity, diaphragm, mediastinum
both produce serous fluid
pleural cavity - ANSWER-space between serous membranes
lubricated to decrease friction during expansion/recoil
explain the functional importance of the increased surface tension between the
serous membranes (in the pleural fluid) of the pleural cavities - ANSWER-keeps the
membranes from separating
pulls lungs outward toward thoracic wall
opposes lung collapse
intrapulmonary pressure - ANSWER-pressure in alveoli
increases/decreases during breathing
always equalizes with atmospheric pressure
intrapleural pressure - ANSWER-pressure in the pleural cavity
increases/decreases during breathing
always is 4 mm Hg less than intrapulmonary pressure
- results in a negative intrapleural pressure
- means the outward pull on the lungs are greater than the forces causing collapse
(like elastic recoil, etc.)
pneumothorax - ANSWER--air in pleural cavity
-intrapleural pressure becomes equal to atmospheric pressure, results in atelactasis
(collapsed lung)
describe the blood supply to the lungs - ANSWER-pulmonary circulation:
, - pulmonary arteries -> pulmonary capillary networks surrounding alveoli
- pulmonary veins - carry oxygenated blood to left atrium
bronchial circulation:
- aorta -> bronchial arteries -> provide systemic blood to lung tissue (except alveoli)
- bronchial veins -> axygous -> SVC -> RA
- bronchial veins -> pulmonary veins -> LA
explain how the structure of the respiratory membrane maximizes gas transport -
ANSWER-thin alveolar/capillary walls for easy gas exchange/diffusion
both walls are made of simple squamous epithelial cells w/ thin basement membrane
define Boyle's Law - ANSWER-pressure of a gas is inversely proportional to its
volume at a given temp
using Boyle's Law, explain how pressure and volume change during inspiration and
expiration to cause air movement into and out of the lungs - ANSWER-when alveolar
volume increases, pleural pressure decreases below atmospheric pressure and air
moves into the lungs
when alveolar volume decreases, pleural pressure increases above atmospheric
pressure and air moves out of the lungs
identify the skeletal muscles involved in normal inspiration and indicate the specific
effect on thoracic volume and pressure - ANSWER-diaphragm moves inferiorly and
lowers thoracic floor (75%)
external intercostals elevates (up and out) ribs and sternum flares (25%)
inspiratory muscles contract (diaphragm descends and rib cage rises) --> thoracic
cavity vol increases --> lungs are stretched, intrapulmonary vol increases -->
intrapulmonary pressure drops to -1 mm Hg --> air flows into lungs down its pressure
gradients until intrapulmonary pressure is 0 (equal to atmospheric pressure)
inspiration is always ________, requiring ______ to stimulate skeletal muscle
contraction - ANSWER-active, somatic motor neurons
identify the skeletal muscles involved in normal expiration and indicate the specific
effect on thoracic volume and pressure - ANSWER-inspiratory muscles relax
(diaphragm rises, rib cage descends due to recoil of costal cartilages) --> thoracic
cavity vol decreases --> elastic lungs recoil passively --> intrapulmonary vol
decreases --> intrapulmonary pressure rises to +1 mm Hg --> air flows out of lungs
down its pressure gradient until intrapulmonary pressure is 0
identify the skeletal muscles involved in forced inspiration (hyperpnea) and indicate
the specific effect on thoracic volume and pressure - ANSWER-contracts additional
skeletal muscles to increase or decrease thoracic volume more and create larger
pressure gradients
scalenes and pectoralis minor: pull ribs inward
sternocleidomastoids: pull up on sternum
erector spinae: extension of vertebral column
Correct Answers
describe the major features of the respiratory mucosa - ANSWER--mucous
membrane
-epithelium and lamina propia
-mucus
- goblet cells
- glands in connective tissue
-may have cilia
-epithelium - variable
list the paranasal sinuses - ANSWER-frontal, ethmoidal air cells, sphenoidal,
maxillary
auditory tubes of the nasopharynx - ANSWER-eustachian, pharyngotympanic
which vocal cords are inelastic? - ANSWER-vestibular folds
which vocal cords are elastic? - ANSWER-vocal folds
vocal cords: sound production - ANSWER-via vocal fold vibrations
cartilage in the larynx - ANSWER-epiglottis: elastic cartilage
thyroid + cricoid: hyaline cartilage
what alters the diameter of the trachea? - ANSWER-ANS, controls the trachealis
smooth muscle
where do the primary bronchi enter the lung? - ANSWER-hilum
also where blood vessels, lymphatic vessels, nerves and bronchi enter the lung
describe the lungs - ANSWER-R: 3 lobes
L: 2 lobes
- divided by fissures (R: horizontal and oblique, L: oblique)
- air filled spaces surrounded by elastic tissue
- enclosed in pleural cavity filled with small amount of fluid which decreases friction
describe the functional importance of the lung being divided into bronchopulmonary
segments - ANSWER-each bronchopulmonary segment has its own air supply,
blood supply, and lymphatic vessels, surrounded by connective tissue
describe the anatomical changes that occur along the branching of the respiratory
structures - ANSWER--smooth muscle increases
-cartilage decreases: C-shaped rings to plates
,-smaller diameter
-thinner epithelium
tissue of the bronchioles - ANSWER-simple cuboidal epithelium
smooth muscle controlled by ANS
sparse to no cilia
respiratory pathway through alveoli - ANSWER-terminal bronchiole -> respiratory
bronchioles -> alveolar duct -> alveolar sacs of many alveoli
explain the functional importance of decreasing surface tension in the alveoli -
ANSWER-keeps alveoli from collapsing, makes them easier to inflate
alveolar cells - ANSWER-macrophages
alveolar type 1: simple squamous epithelial cells, alveolar pores (equalize pressure
between alveoli)
alveolar type 2: epithelial cells that secrete surfactant, decrease surface tension to
keep alveoli from collapsing making them easier to inflate
visceral pleura - ANSWER-membrane on outside of lung
produces serous fluid
parietal pleura - ANSWER-lines wall of thoracic cavity, diaphragm, mediastinum
both produce serous fluid
pleural cavity - ANSWER-space between serous membranes
lubricated to decrease friction during expansion/recoil
explain the functional importance of the increased surface tension between the
serous membranes (in the pleural fluid) of the pleural cavities - ANSWER-keeps the
membranes from separating
pulls lungs outward toward thoracic wall
opposes lung collapse
intrapulmonary pressure - ANSWER-pressure in alveoli
increases/decreases during breathing
always equalizes with atmospheric pressure
intrapleural pressure - ANSWER-pressure in the pleural cavity
increases/decreases during breathing
always is 4 mm Hg less than intrapulmonary pressure
- results in a negative intrapleural pressure
- means the outward pull on the lungs are greater than the forces causing collapse
(like elastic recoil, etc.)
pneumothorax - ANSWER--air in pleural cavity
-intrapleural pressure becomes equal to atmospheric pressure, results in atelactasis
(collapsed lung)
describe the blood supply to the lungs - ANSWER-pulmonary circulation:
, - pulmonary arteries -> pulmonary capillary networks surrounding alveoli
- pulmonary veins - carry oxygenated blood to left atrium
bronchial circulation:
- aorta -> bronchial arteries -> provide systemic blood to lung tissue (except alveoli)
- bronchial veins -> axygous -> SVC -> RA
- bronchial veins -> pulmonary veins -> LA
explain how the structure of the respiratory membrane maximizes gas transport -
ANSWER-thin alveolar/capillary walls for easy gas exchange/diffusion
both walls are made of simple squamous epithelial cells w/ thin basement membrane
define Boyle's Law - ANSWER-pressure of a gas is inversely proportional to its
volume at a given temp
using Boyle's Law, explain how pressure and volume change during inspiration and
expiration to cause air movement into and out of the lungs - ANSWER-when alveolar
volume increases, pleural pressure decreases below atmospheric pressure and air
moves into the lungs
when alveolar volume decreases, pleural pressure increases above atmospheric
pressure and air moves out of the lungs
identify the skeletal muscles involved in normal inspiration and indicate the specific
effect on thoracic volume and pressure - ANSWER-diaphragm moves inferiorly and
lowers thoracic floor (75%)
external intercostals elevates (up and out) ribs and sternum flares (25%)
inspiratory muscles contract (diaphragm descends and rib cage rises) --> thoracic
cavity vol increases --> lungs are stretched, intrapulmonary vol increases -->
intrapulmonary pressure drops to -1 mm Hg --> air flows into lungs down its pressure
gradients until intrapulmonary pressure is 0 (equal to atmospheric pressure)
inspiration is always ________, requiring ______ to stimulate skeletal muscle
contraction - ANSWER-active, somatic motor neurons
identify the skeletal muscles involved in normal expiration and indicate the specific
effect on thoracic volume and pressure - ANSWER-inspiratory muscles relax
(diaphragm rises, rib cage descends due to recoil of costal cartilages) --> thoracic
cavity vol decreases --> elastic lungs recoil passively --> intrapulmonary vol
decreases --> intrapulmonary pressure rises to +1 mm Hg --> air flows out of lungs
down its pressure gradient until intrapulmonary pressure is 0
identify the skeletal muscles involved in forced inspiration (hyperpnea) and indicate
the specific effect on thoracic volume and pressure - ANSWER-contracts additional
skeletal muscles to increase or decrease thoracic volume more and create larger
pressure gradients
scalenes and pectoralis minor: pull ribs inward
sternocleidomastoids: pull up on sternum
erector spinae: extension of vertebral column
