Ch 12: The Respiratory System and the Skin Flashcards
Simple multicellular organisms such as _________ (jellyfish and hydra) can still receive sufficient oxygen by diffusion between cells and the environment.
coelenterates
p. 440
Simple movement of air into and out of the lungs is properly called _________, whereas the actual exchange of gases is called __________.
ventilation
respiration
p. 440
What part of glucose metabolism produces CO2?
pyruvate dehydrogenase and the Krebs cycle, during cellular respiration
p. 440
Inhaled air follows this pathway: nose –> nasal cavity –> pharynx –> _______ –> trachea –> bronchi –> terminal bronchioles –> _______ _______ –> alveolar ducts –> alveoli.
larynx
respiratory bronchioles
p. 441
Which structures are the smallest and final branches of the conduction zone?
terminal bronchioles
p. 441
What type of epithelia line the conduction zone of the respiratory tract?
Within this epithelia are specialized cells that secrete mucus; these are called ______ cells.
tall columnar epithelia
goblet
p. 443
What are the gas-exchanging surfaces of the lungs lined with?
What type of cells are these?
simple squamous epithelia
Type 1 alveolar cells.
p. 443
Does surfactant increase or decrease surface tension on alveoli?
What type of cell secretes surfactant?
It decreases surface tension, making them easier to inflate.
Type 2 alveolar cells (these are fat, cuboidal epithelial cells).
p. 444
The expansion of the chest during inspiration is driven primarily by _________ of the diaphragm.
contraction
p. 446
Resting expiration is a _______ process (no muscle contraction required), while forced expiration is an ______ process.
passive
active
p. 446
Where does pressure become negative or more negative during inspiration?
The pleural pressure becomes more negative, and pressure in the alveoli becomes negative.
p. 447
What becomes impossible when a lung collapses?
inspiration
p. 447
Tidal volume is equal to about __% of the total volume of the lungs.
Example values?
10%
- 5 L TV out of 5 L total volume
p. 448
Total lung capacity is the sum of….
….vital capacity plus residual volume.
p. 448
An interesting feature of emphysema is that lung elasticity gets reduced, and since there is less of a recoil force drawing alveoli inward, the pleural pressure will be ____ negative.
less
p. 448
Why don’t the lipid bilayers of the alveolar and capillary cells act as barriers to the diffusion of oxygen and carbon dioxide?
Because they permit small hydrophobic molecules to freely diffuse.
p. 450
During vigorous muscle activity, myoglobin in muscle cells is able to take oxygen from RBC hemoglobin because myoglobin has a ______ ________ for oxygen in this state.
higher affinity
Where is the respiratory control center located?
in the medulla of the brain stem
p. 452
The stimuli that affect ventilation rate are both _________ and ________
mechanical and chemical
p. 452
Peripheral chemoreceptors found in the aorta and carotid arteries monitor the PCO2, pH, and pO2 of the blood, while central chemoreceptors are found in the medullary respiratory control center and monitor pCO2 and pH of the ___ (but not O2). Note that CO2 and pH are the primary regulators and O2 is _________.
CSF
secondary
p. 452
During an allergy attack, mast cells release histamine, which also causes _________.
This is why asthma/allergy medication contains epinephrine, antihistamines, and ___________.
bronchoconstriction
anticholinergics
p. 453
There are irritant receptors in the lung that trigger ________ and/or bronchoconstriction when an irritating chemical (such as smoke) is detected. This contractile response is determined by ___________ nerves that release acetylcholine.
coughing
parasympathetic
p. 453
During inspiration, the diaphragm is _________ and _________, and the ________ intercostal muscles pull the ribs ______ expanding the rib cage.
contracted and flattened
external
upward
If we exhale actively (instead of passively), the ________ intercostal muscles and abdominals pull the rib cage down, decreasing the volume of the thoracic cavity.
internal
