Lecture 13- Respiratory Flashcards
1
Q
is the process of obtaining oxygen from the external environment and eliminating carbon dioxide
A
respiration
2
Q
oxidative processes
within cells
A
cellular respiration
3
Q
exchange of O2 and CO2 between the organism and its environment
A
External respiration
4
Q
Gases ___ ___pressure gradients in the lungs and other organs
A
diffuse down
5
Q
Gases diffuse down as a result of differences in___ ____
A
Partial pressure
6
Q
is the pressure exerted by a particular gas in a mixture of gases
A
Partial pressure
7
Q
Components of gas-transfer system
A
- Breathing movements
- DIffusion of O and CO2 across the respiratory equilibrium
- Bulk transfer of gases by the blood
- Diffusion of O and CO2 across capillary walls
8
Q
Conditions of gas-exchange regions for diffusion to be effective
A
- Moist
- Thin
- Relatively large
- In contact with teh environment
9
Q
Enhances the effectiveness of diffusion
A
Vascularization
10
Q
source of O2 or respiratory medium for animal
A
Air or water
11
Q
Types of breathing
A
- Unidirectional
- Bidirectional or tidal
12
Q
- in most fish gills
- continuous ventilation
- water enters the buccal cavity through the mouth, passes across the gill curtain and exits flowing in one direction
A
Unidirectional
13
Q
– in lung ventilation
- with air entering and exiting through the same channel
- ventilation is not continuous
A
Bidirectional or tidal
14
Q
Patterns of gas exchange
A
- Crosscurrent flow
- Uniform pool
15
Q
- airflow and blood flow cross each other obliquely
- avian lungs
A
crosscurrent flow
16
Q
lung ventilation keep the partial pressure of gases within the alveolar spaces uniform through frequent breathing, mixing gases, and absence of significant
barriers to diffusion
A
Uniform pool
17
Q
in crosscurrent flow, airflow and bloodflow cross each other _____
A
obliquely
18
Q
in uniform pool, where do lung ventilation keeps the partial pressure of gases?
A
Alveolar spaces
19
Q
What are some respiratory organs
A
- Gills or branchia
- Lungs
20
Q
A series of bones in bony fish and chimaeras
- protects the gills, provides facial support, and is used for respiration and feeding
A
Operculum
21
Q
exchange of substance between two fluids in opposite directions
A
Countercurrent flow/exchange
22
Q
system of branching ducts conveys air
to the lungs
A
Respiratory system
23
Q
hair-like projections
- line the primary bronchus to remove microbes and debris form interior of the lungs
A
Cilia
24
Q
alternating inhalation and exhalation or air; ventilates the lungs
A
Breathing
25
A frog ventilates its lungs by ___ ___ ___
Positive pressure breathing
26
what does positive pressure breathing do?
forces air down the trachea
27
How do mammals ventilate their lungs
Negative pressure breathing
28
How does air get to alveoli
Trachea -->Primary bronchi (left, right) --> Secondary bronchi (each
lobe) --> Tertiary bronchi --> bronchioles -->Alveoli
29
envelope the lungs
Pleural cavities
30
carries O2 blood from
each lung to heart
2 pulmonary veins
31
carries dO2 blood to
each lung
1 pulmonary artery
32
The primary muscle of respirations
Diaphragm
33
Function of Diaphragm for Constraction during inspiration
- Increases volume of thoracic cavity
- Decreases pressure of thoracic cavity
- Air moves into lungs (high -> low
presssure)
34
Diaphragm function during forced contraction (voluntary)
Used for defecation, urination and labor
35
How does Diaphragm works for defecation, urination and labor
- Increases pressure in abdominal cavity
- Pushes on abdominal organs to move contents out
36
Lift ribs to expand chest cavity for inspiration
Intercostal muscles
37
no blind ended alveoli in and out of which air moves
Avian lungs
38
voluminous, thin walled diverticula of the lungs which penetrate the centra (pneumatic foramina) except in ratites
Air sacs
39
___ of the lungs extensively distributed throughout of the body
Diverticula
40
Where do gas transfer in birds takes place?
Small air capillaries
41
have the most efficient
vertebrate lungs
Birds
42
In bird respiratory system; ____ ____ allow oxygen-rich air to pass ____ ____ on both inhalation and
exhalation
Air sacs
Respiratory surfaces
43
Control of breathing can be:
- Chemical
- Nervous
44
Chemical control of breathing is dependent to
- Blood CO2 levels
- pH
- Chemoreceptors
45
Control of breathing; Chemoreceptors
Central : Monitors CSF
Peripheral: Caraotid and aoritic bodies
46
Nervous control of breathing can be..
- Voluntary
- Involuntary
47
Voluntary control of breathing
◦ Cerebral cortex
◦ Protective in nature
◦ Limited control
48
Involuntary control of breathing
- Medullary rhytmicity area
- Pons
49
Maintains basic rhythm of respiration
Medullary rhythmicity area
50
Coordinates transition between inspiration and expiration
Pons
51
Control of Breathing in Humans; when the control center registers a slight drop in pH, it ....
- Increases the depth and rate of breathing
- Excess CO2 is eliminated in exhaled air
52
Facilitates inspiration and helps control depth of inspiration
Apneustic center
53
Helps control rate of respiration
Pneumataxic center
54
- This group maintains the basic rhythm of respiration.
- The pons coordinates transition between inspiration and expiration.
Brainstem group (involuntary)
55
Cerebral cortex group
Voluntary
56
Influence the timing of inspiratory cut-off by providing a tonic input to the respiratory pattern generators located in the inspiratory center
Pneumotaxic center
57
Pneumotaxic center influences the respiratory response to what stimuli?
Hypercapnia
Hypoxia
Lung infection
58
- found in the lower pons
- source of impulses that terminate inspiration “inspiratory cut-off switch”
Apneustic center
59
inactivation of Apneustic center results in
apneustic breathing
60
rhythmic respiration
with a marked increase
in inspiratory time and
a short expiration
phase
Apneustic breathing
61
Two groups of medullary center
- Inspiratory dorsal respiratory group (DRG)
- Experiatory ventral respiratory group (VRG)
62
- is the site of projection of proprioceptive afferents from the respiratory muscles and chest wall.
- site of origin of the normal rhythmic respiratory drive consisting of repetitive bursts of inspiratory action potentials.
DRG (inspiratory dorsal respiratory group)
63
innervates respiratory effector muscles through the phrenic,
intercostal, and
abdominal respiratory
motoneurons
ventral respiratory group (VRG)
64
– most important factor
H+ concentration
65
aids the H+ concentration by forming carbonic acid
Carbon dioxide
66
are complexes of proteins and metallic ions
Respiratory pigments
67
oxygen diffuses across the respiratory epithelium into the blood - combines with a
Respiratory pigment
68
most vertebrates and some invertebrates use
Hemoglobin
69
What is the Bunsen solubility coefficient for oxygen in blood at 37°C
- 2.4 ml of oxygen per 100 ml of blood per atmosphere of oxygen pressure
70
What is the concentration of oxygen in a physical solution (not bound to a respiratory pigment) in human blood at normal arterial Po2?
0.3 ml of oxygen per 100 ml blood, or 0.3 vol % oxygen
71
What is the total oxygen content of human arterial blood at a normal arterial Po2
20 vol %
72
How does the combination of oxygen with hemoglobin affect oxygen content in blood
causes a 70-fold increase in oxygen content
73
color of a respiratory pigment changes with its
Oxygen content
74
Color of hemoglobin when loaded with O2
Bright red
75
what color is hemoglobin when it becomes deoxygenated?
Dark maroon-red
76
- tetrameric protein
- four folded polypeptide chains of amino acids
Globin
77
- four iron containing porphyrin prosthetic groups
- transports oxygen
heme
78
Molar weight of Hemoglobin
68,000
79
Hemoglobin is composed of?
Heme and protein globin
80
two dimers, α1β1, and α2β2, each of which is a tightly cohering unit
Globin molecule
81
more loosely connected to each other by salt bridges, except that the two β chains do not touch
Two dimers
82
alters these bridges; conformational changes in the hemoglobin molecule
Oxygenation
83
ferrous state (Fe2+) bound by porphyrin ring of the heme, forming coordinate links with four pyrrole nitrogens
Iron
84
Fe2+ is oxidized to Fe3+; does not bind oxygen; nonfunctional
Methemoglobin
85
reduces methemoglobin to the functional ferrous form
RBC with methemoglobin reductase
86
red color of blood and its oxygen-combining ability
Heme group
87
one hemoglobin molecule binds four oxygen molecules
Oxyhemoglobin
88
form of hemoglobin with absence of O2
Deoxyhemoglobin
89
act either to oxidize hemoglobin or to inactivate methemoglobin reductase, thereby increasing the level of methemoglobin and impairing oxygen transport.
Certain compounds (eg. Nitrated and Chlorates)
90
- formed from the incomplete combustion of carbon dioxide
- interferes with the binding of oxygen to hemoglobin
- has an affinity a higher (200X) affinity to hemoglobin than does oxygen
Carbon monoxide (CO)
91
hemoglobin saturated
with CO
Carboxyhemoglobin
92
Other blood pigments
Hemerythin
Chlorocruorin
Hemocyanin
93
Blood pigments in Priapulida, Brachiopoda, Annelida (violet, Fe2+)
Hemerythrin
94
Blood pigemnts for Annelida; (green,
Fe2+)
Chlorocruonin
95
Blood pigment for (Mollusca, Arthropoda; blue; deoxygenated: colorless; not packaged in cells)
Hemocyanin
96
How many oxygen can hemoglobin carry
- Four oxygen molecules
97
relationship between percent saturation and the partial pressure of oxygen
Oxygen dissociation curves
98
oxygen dissociation curves of other vertebrate
Sigmoid
99
What does P50 represent in terms of hemoglobin's oxygen affinity?
partial pressure of O2 at which the pigment is 50% saturated with O2
100
The lower the ___ the higher the oxygen affinity
P50
101
Condition that Oxygen affinity is reduced
- elevated temperature
- Binding of organic phosphate ligands (DPG, ATP, or GTP by hemoglobin)
- Decrease in pH (increase in H+ concentration)
- Increase in carbon dioxide
102
a change in the oxygen dissociation curve caused by carbon dioxide levels
Bohr effect
103
predominant form of CO2
Bicarbonate (HCO3^-)
104
Total CO2 content varies with
PCO2
105
A decrease in pH at a constant PCO2 is associated with the fall in _____
bicarbonate
106
Most of the bicarbonate in the blood is in the
___
plasma
107
most O2 combines with hemoglobin in red blood cells to form
Oxyhemoglobin
108
some CO2 combines with hemoglobin to form
carbaminohemoglobin
109
CO binds to Hb as
carboxyhemoglobin
110
normal, quiet breathing typical of an animal at rest
Eupnea
111
increase or decrease in the amount of air moved into and out of the lungs by changes in the rate and depth of breathing
Hyperventilation or Hypoventilation
112
increased lung ventilation due to increased breathing in response to elevated carbon dioxide production
Hypernea
113
Absence of breathing
Apnea
114
labored breathing associated with an unpleasant sensation of breathlessness
Dyspnea
115
increase in breathing rate w/o an increase in the depth of breathing
Polypnea
116
Average rate of breathing of an adult
14-20 cycles/minute
117
Rise in temperature will decrease the _____-
Oxygen affinity -> making oxygen transfer between oxygen and blood difficult
118
contains γ chains, rather than adult β chains, has a higher oxygen affinity than adult hemoglobin
Human fetal hemoglobin
119
influenced by properties of the medium and requirements of the
animal
Structure of gas-transfer system
120
minimize diffusion distances in water, creating a thin layer of water over the respiratory surface
Design of fish gills
121
properties of the alveolar wall and the surface tension at the liquid-air interface
Lung wall tension
122
force that tends to minimize the area of a liquid surface
Surface tension
123
- low surface tension of the liquid lining the lungs
- lipoprotein complexes that bestow a very low surface tension on the liquid-air interface
Surfactants
124
predominant lipid in these lipoprotein complexes
Dipalmitoyl lecithin
125
newborns produce no lung surfactants = cannot inflate their lungs at birth without assistance (premature babies)
Newborn respiratory distress syndrome
126
- the volume of air an animal inhales and exhales with each breath
Tidal volume
127
Average tidal volume in resting humans
500 mL
128
- maximum volume of air that can enter the lung;
- about 3.4 L and 4.8 L for college-age females and males, respectively
Vital capacity
129
amount of air that persists in the lungs after maximal expiratory effort
Residual volume
130
sum of residual volume and vital capacity
Total lung capacity
131
tidal volume minus residual volume (anatomic dead-space volume)
Alveolar ventilation volume
132
Respiratory system of Insects and other terrestrial arthropods
- consists of branched tracheae
- Oxygen enters tracheae at spiracles
- Tracheae branch until end in tracheoles that are in direct contact with body cells
133
movement of the ribs, diaphragmaticus muscles and liver
Crocodilians
134
movement of the pelvic girdle
in Turtles
