The Respiratory System III Flashcards
Because oxygen very soluble in plasma, _____% of it must be bound to _____
in order to be carried.
is not; 98; hemoglobin
Each molecule of hemoglobin can carry _____ molecules of oxygen.
four
Hemoglobin that is fully saturated with oxygen is called _____; when no oxygen is bound,
it is called _____.
oxyhemoglobin;
deoxyhemoglobin
As the temperature in the blood increases, the binding of oxygen to hemoglobin _____,
and thus the delivery of oxygen to tissue _____
decreases; increases
As the partial pressure of carbon dioxide in the blood increases, the binding of oxygen to
hemoglobin _____, and thus the delivery of oxygen to tissue _____.
decreases; increases
As blood pH decreases, _____ bind to hemoglobin. This causes the binding of oxygen to
hemoglobin to _____, and thus the delivery of oxygen to tissue to _____. (This is called
the _____.)
hydrogen ions; decrease;
increase; Bohr effect
Red blood cells produce _____ to control the binding of oxygen to hemoglobin.
2,3-bisphosphoglycerate (2,3-
BPG)
Levels of _____ in erythrocytes are increased at high altitudes to enhance oxygen delivery
to tissues.
2,3-bisphosphoglycerate (2,3-
BPG)
As levels of 2,3-bisphosphoglycerate in erythrocytes increase, the binding of oxygen to
hemoglobin _____, and thus the delivery of oxygen to tissue _____.
decreases; increases
With each oxygen molecule that hemoglobin binds, its shape changes to allow it to _____.
This allows it to bind oxygen quickly in the lungs, and to release it quickly in oxygen-poor
tissues.
bind the next one with higher
affinity
Most tissues don’t need nearly as much oxygen as hemoglobin can carry; however, in
_____, including the _____, the partial pressure of oxygen is very low and most of
hemoglobin’s oxygen is released.
active muscle tissue; heart
The partial pressure of carbon dioxide in the alveoli is _____ than in the blood.
slightly lower
The partial pressure of carbon dioxide in the tissues is always _____ than in the blood.
higher
70% of the carbon dioxide in the blood is transported as _____; conversion of carbon
dioxide to this chemical dramatically increases the rate at which carbon dioxide can be
removed from tissue and transported to the lungs.
bicarbonate ions
20% of the carbon dioxide in the blood is transported by _____; 10% or so is found _____.
hemoglobin; in the blood
plasma
____ refers to an elevation in carbon dioxide levels in the blood.
Hypercapnia
As the oxygen saturation of hemoglobin _____, its ability to carry carbon dioxide _____.
This is known as the _____.
decreases; increases; Haldane
effect
The reaction that forms carbonic acid is: _____.
CO2
+ H2O –> H2CO3
. Carbonic acid dissociates to form _____ and _____. This reaction is _____.
hydrogen ions OR H+ ; bicarbonate OR HCO3 - ; reversible
Much of the bicarbonate in the body is produced by _____.
erythrocytes
Formation of carbonic acid in an aqueous solution is spontaneous but slow. In
erythrocytes, where it must occur quickly, it is _____.
catalyzed by an enzyme
The carbonic acid/bicarbonate interconversion is \_\_\_\_\_, and this allows bicarbonate to act as a(n) \_\_\_\_\_ in the bloodstream. Indeed, it is the most important one!
reversible; buffer
As negative bicarbonate ions leave erythrocytes, negative _____ ions enter to maintain
the electrical neutrality of the cell. This is called the _____.
chloride; chloride shift
Normal, quiet breathing, at a typical ventilation rate, is called _____.
eupnea
Difficult or labored respiration is called _____.
dyspnea
Absence of breathing is called _____.
apnea
Deep, vigorous respiration, common during exercise, is called _____.
hyperpnea
The _____ center, located in the medulla, contains two groups of neurons which control
respiration: the _____ and the _____ groups.
medullary respiratory; dorsal
respiratory; ventral respiratory
The dorsal respiratory group, located in the _____, generates _____ which stimulate
contraction of the _____.
medulla; rhythmic nerve
impulses; diaphragm
Although unproven, current thinking holds that nerve impulses from the _____ group not
only instigate inspiration but also lead to its time-delayed inhibition.
dorsal respiratory
The ventral respiratory group, located in the _____, is required during forceful breathing to
recruit the _____.
medulla; intercostal and
abdominal muscles
The pontine respiratory group, located in the _____, is thought to _____ and prevent
_____ by inhibiting the medullary respiration centers.
pons; modify the breathing
rhythm; overinflation of the
lungs
When the chemoreceptors in the _____, _____ and _____ sense an increase in levels of
carbon dioxide in the blood, they signal the respiratory control center to _____ the
breathing rate.
medulla oblongata; carotid
arteries; aorta; increase
When the chemoreceptors in the _____, _____ and _____ sense a decrease in the pH of
the blood, they signal the respiratory control center to _____ the breathing rate.
medulla oblongata; carotid
arteries; aorta; increase
When the chemoreceptors in the _____, _____ and _____ sense an increase in levels of
hydrogen ions in the blood, they signal the respiratory control center to _____ the
breathing rate.
medulla oblongata; carotid
arteries; aorta; increase
Of the three major chemoreceptor clusters, detection of _____ by the _____ exerts the
most control on breathing rate.
carbon dioxide; medulla
oblongata
When the chemoreceptors in the _____ and _____ sense a decrease in levels of oxygen
in the blood, they signal the respiratory control center to _____ the breathing rate.
carotid arteries; aorta; increase
When stretch receptors in the walls of the bronchi and bronchioles are _____, inspiration
is discontinued in a reflex called the _____ or _____.
fully stretched; Hering-Breuer
reflex; inflation reflex
Pulmonary irritant reflexes respond to irritation of the respiratory tract by causing _____,
followed by increased _____ and _____ through the irritated passageway. Examples
include coughing and sneezing.
reflex constriction of the glottis;
pulmonary pressure; explosive
release
The cerebral cortex can exert voluntary control over respiration by bypassing the
medullary centers and _____.
directly stimulating the
respiratory muscles
Sympathetic centers in the _____ modify the ventilation rate and depth in response to
strong emotions, abrupt temperature changes, and pain.
hypothalamus
Anaerobic exercises causes a dramatic increase in ventilation rate due to the production
of _____, which lowers _____. Indeed, respiration is so rapid that carbon dioxide levels
may be _____, and oxygen levels _____, than their resting levels.
lactic acid; blood pH; lower;
higher
Aerobic exercise alters breathing rate within seconds, in part due to direct communication
between _____ and the _____.
motor pathways; medullary
respiratory center
Aerobic exercise alters breathing rate within seconds, in part due to signals sent from
_____ to the _____, informing it of the body’s exertion.
proprioceptors in the body;
medullary respiratory center
After the initial rapid increase in ventilation rate, aerobic exercise causes a slow,
sustained increase. ‘How’ remains unknown, but it is NOT due to changes in average
_____, nor to changes in _____ or _____ concentrations, which remain constant.
blood pH; oxygen; carbon
dioxide
Adaptations to high altitudes include an increase in _____, elevated _____, and increased
production of erythropoietin (and thus of _____).
ventilation rate; 2,3-BPG; RBCs
'’COPD’’ refers to a group of diseases that result in chronic and progressive dyspnea,
often accompanied by coughing, frequent pulmonary infections, and respiratory failure.
The acronym means, ‘_____.’
chronic obstructive pulmonary
diseases
Obstructive emphysema is a COPD which is characterized by _____ and _____.
permanently enlarged alveoli;
deterioration of alveolar walls
Chronic bronchitis is a COPD which results in _____, as well as inflammation and fibrosis
of the _____.
excessive mucus production;
lower respiratory mucosa
Although asthma is a chronic disease, it is not classified as a “COPD” because the
symptoms are not chronic. Asthma is characterized by acute attacks of coughing,
dyspnea, wheezing, and chest tightness, brought on by _____.
acute inflammation of the
airways
_____ is an infectious disease caused by the bacterium Mycobacterium tuberculosis and
spread by coughing and inhalation.
Tuberculosis (TB)
Until the 1930s, one third of the deaths in the 20-45 year old age group were due to
_____. Antibiotics changed that, but the use of these drugs in ways which allowed one or
more bacteria to survive has led to the evolution of _____.
tuberculosis (TB); antibiotic
resistant strains
As of the year 2000, one third of all cancer deaths are due to _____: only one in ten
affected individuals is a non-smoker, highlighting the contribution of smoking to the
development of the disease.
lung cancer
One of _____ types of lung cancer, squamous cell carcinoma arises in the _____, and
tends to form masses that hollow out and bleed.
three; epithelium of the bronchi
One of _____ types of lung cancer, adenocarcinoma originates in _____ as nodules that
develop from _____ and _____.
three; peripheral lung areas;
bronchial glands; alveolar cells
One of _____ types of lung cancer, small cell carcinoma contains _____ cells that form
clusters within the _____ and rapidly metastasize.
three; lymphocyte-like;
mediastinum
As we age, the thoracic wall becomes _____, the lungs lose _____, and the amount of
oxygen we can use during aerobic respiration decreases. These changes are accelerated
markedly in _____ individuals.
more rigid; elasticity; inactive
The protection provided by mucus declines with age due to alterations in _____, and a
decline in the _____ of epithelial cells in the respiratory tract.
mucous glands; ciliary action
