the amount of air entering and leaving the lungs with each breath
tidal volume
the process by which air is moved in and out of the lungs
pulmonary ventilation
process by which gases are exchanged across the respiratory membrane in the alveoli
pulmonary diffusion
_________ is transported in the blood primarily bound to _____________(as ______________), although a small part of it is dissolved in _________
oxygen
hemoglobin
oxyhemoglobin
plasma
To better respond to increased oxygen demand, hemoglobin unloading of oxygen (desaturation) is enhanced when ____ decreases, ___ decreases, or ___________ increases.
PO2
pH
temperature
The amount and rate of ___ ____________that occur across the membrane depend primarily on the _________ __________ of each gas, although other factors are also important, as shown by Fick’s law. Gases diffuse along a _________ _________, moving from an area of ________ pressure to one of _______ pressure. Thus, ________ enters the blood and ________ ________ leaves it
gas exchange
partial pressure
pressure gradient
higher
lower
oxygen
carbon dioxide
Carbon dioxide is transported in the blood primarily as _____________ ___. This prevents the formation of ____________ ____, which can cause _____ to accumulate and _______ the pH. Smaller amounts of carbon dioxide are either dissolved in the ________ or bound to ____________
bicarbonate ion
carbonic acid
H+
lower
plasma
hemoglobin
The difference in the oxygen content of arterial and mixed venous blood throughout the body. This measure reflects the amount of oxygen taken up by the tissues, active and inactive.
AVO2 difference
Carbon dioxide exchange at the tissues is similar to oxygen exchange, except that carbon dioxide leaves the ________, where it is formed, and enters the _______ to be transported to the _______ for clearance.
muscles
blood
lungs
Cardiovascular response to acute exercise
As exercise intensity ____________, HR ___________ proportionately, approaching ________ ______ ____ near the maximal exercise intensity
increases
increases
heart rate max
Cardiovascular response to acute exercise
Stroke volume also ___________ proportionately with _____________ exercise intensity but usually achieves its maximal value at about ___% to ___% of __________ in untrained individuals. Highly trained individuals can continue to increase ______ ______, sometimes up to maximal exercise intensity
increases
increasing
40%
60%
VO2max
stroke volume
Cardiovascular response to acute exercise
Increases in _______ _______ and _______ ________ combine to increase cardiac output.
Thus, more ________ is pumped during _________, ensuring that an adequate supply of _________ and __________ _________ reaches the exercising muscles and that the ________ _________of muscle metabolism are cleared away.
heart rate
stroke volume
blood
exercise
oxygen
metabolic substrates
waste products
Cardiovascular response to acute exercise
During exercise, _________ __________ increases in proportion to exercise _________ to match the need for increased _______ _______ to exercising muscles.
cardiac output
intensity
blood flow
Cardiovascular response to acute exercise
According to the ____ _________, whole-body oxygen consumption (VO2) is calculated as the product of the _________ ________ and _____ ____________
fick equation
cardiac output
avo2 difference
Cardiovascular response to acute exercise
Mean arterial blood pressure __________ immediately in response to __________, and the magnitude of the __________ is proportional to the __________ of exercise
During whole-body endurance exercise, this is accomplished primarily by an increase in _________ blood pressure, with minimal changes in _________ pressure
increases
exercise
increase
intensity
systolic
diastolic
Cardiovascular response to acute exercise
____________ is redistributed during exercise from inactive or low-activity tissues of the body like the ______ and _________ to meet the increased _________ needs of exercising muscles
blood flow
liver
kidneys
metabolic
Cardiovascular response to acute exercise
With prolonged _________ exercise, or aerobic exercise in the ______, __________ _________ gradually decreases and _______ ___________ increases proportionately to maintain _________ _________. This is referred to as ____________ ______ and is associated with a progressive increase in ______ _______ to the __________ ____ and losses of fluid from the ___________ _______
aerobic
heat
stroke volume
heart rate
cardiac output
cardiovascular drift
blood flow
vasodilated skin
vascular space
changes that occur in the blood during exercise
The avo2 difference increases as ______ ________ concentration decreases, reflecting increased __________ of oxygen from the ______ for use by the ________ tissues.
increases
venous oxygen
extraction
blood
active
changes that occur in the blood during exercise
________ ________ decreases because plasma is pushed out of the _________ by increased _________ _________ as _______ _________ increases, and _______ is drawn into the muscles by the increased __________ and ________ pressures in the muscle tissues, a by-product of metabolism.
With prolonged exercise or exercise in hot environments, increasingly more _______ _______ is lost through ___________
plasma volume
capillaries
hydrostatic pressure
blood pressure
fluid
oncotic
osmotic
plasma volume
sweating
changes that occur in the blood during exercise
________________ occurs as _______ ________ (water) decreases. Although the actual number of red blood cells stays relatively constant, the ________ number of red blood cells per unit of _______ increases, which increases ________ _________ capacity.
hemoconcentration
plasma volume
relative
blood
oxygen carrying
Respiratory response to acute exercise
During exercise, _____________ shows an almost immediate increase due to increased _________ __________ stimulation. This is caused by both central command and neural feedback from muscle activity itself.
This phase is followed by a plateau during ______ __________ or a much more gradual increase in respiration during _______ _________ that results from _______ __________ in the _______ _________ resulting from exercise metabolism.
ventilation
inspiratory center
light exercise
heavy exercise
chemical changes
arterial blood
Respiratory response to acute exercise
During mild, steady-state exercise, ____________ increases to match the rate of ________ ___________; that is, _________ parallels __________ ________
ventilation
energy metabolism
ventilation
oxygen uptake
Respiratory response to acute exercise
At low exercise intensities, increased ventilation is accomplished by increases in ______ _________(the amount of air moved in and out of the lungs during regular breathing). At higher intensities, the ____________ _____also increases
tidal volume
respiratory rate
Respiratory response to acute exercise
Maximal rates of pulmonary ventilation depend on _____ ______
body size
Respiratory response to acute exercise
The ________ __________ is the point at which ventilation begins to _________ disproportionately to the increase in _________ ___________ This increase in ventilation reflects the need to remove excess ____________ _________
ventilatory threshold
increase
oxygen consumption
carbon dioxide
Respiratory response to acute exercise
_________ occurs with shortness of breath or difficulty breathing during exercise due to elevation of CO2 and H+ and or unconditioned ventilatory musculature
an increased __________ ________
and decreased ________ ________
Dyspnea
respiratory rate
tidal volume
Respiratory response to acute exercise
______________ occurs with increased ventilation in excess represented during anaerobic threshold and highly anaerobic activity resulting in an elevated ____________ _____ and ______ ___________
hyperventilation
breathing rate
tidal volume
Respiratory response to acute exercise
___________ ___________ is holding breath against a closed glottis usually seen in high anaerobic activities involving strength and power results in high intraabdominal and thoracic pressures decreasing ________ _________
valsalva maneuver
venous return