Respiration During Exercise Ch. 10

what are the structures of the respiratory system

- Nose and nasal cavities - pharynx and larynx - trachea and bronchial tree - lungs *alveoli site of gas exchange*

deoxyhemoglobin + O2 <---> Oxyhemaglobin the direction of this reaction depends on

- Partial pressure O2 (PO2) of the blood - Affinity between HB and O2

Function of the respiratory system

- Replacing O2 - Removing CO2 - Regulation of Acid-base balance

what are the causes of cardiovascular drift?

- The influence of rising body temp on dehydration - a reduction in plasma volume

Identify the areas of the brain stem in which the respiratory control center is located

- The medulla oblongata - the pons

The Bohr effect

- decrease in pH(making it more acidic) lowers HB O2 affinity - results in a right-ward shift of the curve (less oxyhemaglbin affinity) - favors off loading of O2 to tissues

What processes occurred during the exchange of oxygen and carbon dioxide between the lung and the blood?

- diffusion - ventilation

At the lungs ther is a _____ PO2

- high PO2 - it forms oxyhemoglobin

conducting zone function

- humidifies - warms - filters air

According to the Fick's law of diffusion, why is the lung an ideal organ for gas exchange?

- the alveoli membrane in the lung is extremely thin - the total surface are available in the lugs for diffusion is large

spirometry

- the measurement of pulmonary volumes and rates of expired airflow. - used for diagnosing long diseases such as chronic obstructive pulmonary disease COPD - can measure: vital capacity, forced expiratory volume (FEV1) an FEV1/VC ratio

Identify the structure and the conducting zone of the human respiratory SYSTEM

- trachea - bronchial tree - bronchioles

in the context of the O2 transport in blood, the strength of the bond between O2 and hemoglobin is _________.

- weakened by a decrease in blood PH - we more acidic - we wanna give the tissues the O2 ex. during exercise

what are the Humoral(blood borne) chemoreceptors?

1. Central chemoreceptors 2. Peripheral chemoreceptors

respiratory muscle drive is controlled by _______(1)________ neurons in the spinal cord. in the ___(2)____ and ___(3)____.

1. Somatic motor 2. medulla oblongata 3. pons

The ideal ventilation to perfusion ratios (V/Q) is __________ or slightly greater.

1.0

The pressure that each gas exerts independently can be calculated by multiplying the fractional composition of the gas by the _____________.

Absolute pressure

The function of the respiratory zone is to ________________________

Act as the site gas exchange between the Aveoli and the blood

Residual Volume (RV)

Amount of air remaining in the lungs after a forced exhalation

Light to moderate exercise results in what to the V/Q relationship?

An improvement

what is the main way CO2 is transported ?

Bicarbonate 70%

During prolongs the maximal exercise any hot or humid environment ventilation tends to drift upwards due to an increase in ______________

Blood temperature

what does an inhaler do?

Bronchial dilator to let more air in

Carotid bodies

Chemoreceptors located in the internal carotid artery they're sensitive to increase in blood potassium levels, norepinephrine, decrease in arterial PO2 and increase in body temperature

In the respiratory system, the movement of respiratory gases in the blood between the lines and the cells of the body is known as ____________.

Circulatory transport

The most important variable contributing to airway resistance is the ___________

Diameter of the airway

Amount of air in excess tidal volume(TV) that can be exhaled with maximum effort.

Expiratory Reserve Volume (ERV) *The amount of we have to breath all the way out from normal breathing(TV)

The rate of gas transfer Is proportional to the tissue area, the diffusion coefficient of the gas, and in partial pressure of the gas on the two sides of tissues, and is inversely proportional to the thickness. This is known as _______________.

Fick's law of diffusion

In untrained or mod. trained subjects, at work rates greater than 40%-60% VO2 the rise in cardiac output is achieved by INCREASES in ______________.

HR alone

Heavy exercise may result in a ______ V/Q ____________.

Heavy exercise may results in a small V/Q any quality and in mind or impairment in gas exchange

Approximately 99% of oxygen transported to the blood it's chemically bound to ___________

Hemoglobin

Growing evidence suggests that the pulmonary system may limit exercise performance during _____________________________ exercise at sea level

High-intensity

Increase partial pressur of CO2 (PCO2) = __________ breathing

Increase in breathing - The more CO2 we detect the more we will breath

At the beginning of the constant load submaximal exercise, there is an initial rapid _______________

Increase in ventilation

Temperature's effect on O2-HB dissociation curve

Increased Blood temp: - lowers HB O2 affinity - results in Rightward shift of the curve

Amount of air in excess of TV that can be inhaled with max effort.

Inspiratory Reserve Volume (IRV) *How much room we have to take a deep breath from regular breathing

At a constant PH the affinity of HB for O2 is ___________.

Inversely related to blood temp.

Pulmonary Respiration

LUNGS - Ventilation(breathing) - Exchange of O2 and CO2 in the Lungs

Central chemoreceptors Located? Function?

Located: Medulla sensitive to: PCO2 an H+ concentration in cerebrospinal fluid

When compared to systemic circuit, the pulmonary circuit has a ________

Low pressure due to a low vascular resistance in the pulmonary circulation. During exercise the resistance and the pulmonary vascular system falls due to distention of vessels and the recruitment of previously unused capillaries. This decrease in pulmonary vascular resistance results in increased lung blood flow during exercise with a relatively small increase in pulmonary arterial pressure

Diaphram

Major muscle of INSPIRATION by pulling the lungs down

Oxygen transport in muscle is carried out by the oxygen binding protein called ___________

Myoglobin in the muscle cells

How do we ship O2 to mitochondria?

Myoglobin in the muslce cells (think of Muscles) shuttles O2 from the cell membrane to the mitochondria

input to the respiratory control center can be classified into

Neural and humoral

The primary drive to increase ventilation during exercise is due to ______________.

Neural input from Higher brain centers

The primary drivers increased ventilation during exercise is due to _________

Neural input from higher brain centers

risidual volume

O2 reserve to keep the lungs from collapsing

acid-base balance is maintained by an increase in pulmonary ventilation, which causes exhalation of additional CO2 and results in an increase in _______.

PH

Carotid bodies also promote increasing ventilation as a response to increasing blood levels of ___________.

Potassium

The amount of air moves in or out of the lungs per minute(V)

Pulmonary Ventilation (AKA: Minute Ventilation) *Process of moving air in & out of the lungs.-depend on. Frequency and. Tidialvolume

aortic bodies

Receptors located in the arch of the aorta and are capable of sensing changes in the blood levels of CO2 indirectly and therefore these chemoreceptors could play an important role and controlling of breathing I Rest and during exercise

Contraction and relaxation of the respiratory muscles are directly controlled by _____________

Somatic neurons in the spinal cord

The technical use for measuring pulmonary volumes in the human body is known as _____________

Spirometry

T/F in elite athletes, there are low levels of PO2 near maximal work

T Hypoxemia likely due to less time for gas diffusion due to high cardiac output

T/F training reduces the Ventilatory response to exercise

T when we more trained we don't breath as much

Cellular Respiration

TISSUES - O2 Utilization - CO2 production by the tissues

the lungs Requires no muscular effort during expiration

TRUE Requires no muscular effort because both the lung and the chest wall are elastic and returned to the equilibrium position after expanding during inspiration. (the muscles relax)

T/F Myoglobin (MB) has a higher affinity for O2 than hemoglobin even at low PO2

TRUE bc of this it is able to discharge its O2 at very low PO2 values

Forced Expiratory Volume (FEV)

The maximal volume of air exhaled in a specified period of time: usually the 1st sec. during maximal expiration

Bulk flow is the movement of molecules along a passageway due to to____________

The pressure difference between the end of the passageway

The amount of gas moved per breath is called ________________

Tidal volume

Amount of air moved per breath

Tidal volume (Vt) *Normal breathing looks like waves V=f x Vt

The Primary purpose of the respiratory system is to _______

To provide a means of gas exchange between the atmosphere and the body

T/F 99% of O2 is transported bound to HB

True

T/F we are more driven to breath bc of increase CO2 production than O2

True

T/F when the diaphragm contracts it pulls the lungs down

True, it dose this to allow the lungs to fully expand

T/F ventilation is lower during exercise following training

True: exercise ventilation is 20%-30% lower at the same submaximal work rate (when we are more trained we aren't huffing and puffing, we control our breathing, we don't need to breath in as much O2)

How is Tidal volume measured? (formula)

V= f x Vt

How is vital capacity measured? Formula

VC= (ERV + TV + IRV)

During an incremental exercise test, ventilation increases as a linear function of oxygen uptake up to 50% to 70% O2 max, where ventilation begins to rise exponentially. This VE "inflection point" has been called in the ___________________

Ventilatory threshold just above lactate threshold

What is the site and zone of gas exchange?

alveoli is the site in the respiratory zone

Vital capacity

amount of air that can be forcefully exhaled following max inspiration. (NOT the residual volume) *Deep breath in & out VC= (ERV + TV + IRV)

the increase in cardiac output during exercise in the upright position is achieved by an increase in ______.

both stroke volume and HR

Movement of air from the environment to the lungs it's called pulmonary ventilation and it occurs via the process known as ________________

bulk flow

In order to transport CO2 in the blood, under high PCO2 conditions, CO2 combines with water to form carbonic acid. This reaction is catalyzed by the enzyme ___________

carbonic anhydrase

Why is it good that only 20% of HB carries CO2?

good soo that we can use HB more for carrying O2

Whats important about the difference in partial pressure? P1-P2

helps us determine how much of this gas flows into lungs, from lungs -> Blood -> tissues-> blood-> lungs

our submaximal exercise primary dirve to increase ventilation comes from __________.

higher brain centers (central command)

The rising blood lactate that occurs during incremental exercise may be the cause of the alinear rise in the ventilatory because the carotid bodies that increase threshold can be simulated by an ________________

increase in Hydrogen levels

The secondary factor that may contribute to ventilatory control during heavy exercise is a ____________.

increase in blood potassium levels

Partial pressure of O2 (PO2) is ______________ to breathing

inversely proportional

systemic gas exchange

it is the movement of respiratory gases (via diffusion) from the blood into the cells of the body

Define Hypoxemia

low levels of O2 in blood

Total Lung capacity (TLC)

max inhale followed by max exhale until the lungs collapse ( past residual volume)

Motor neuron activity, is directly controlled by the respiratory control center in the ____________

medulla oblongata

where does neural input come from?

motor cortex and skeletal muscle receptors

During active FORCED expiration the muscles in the abdomen wall will work to __________

move diaphragm upwards

Which has a higher affinity for O2, Hemoglobin or Myoglobin?

myoglobin, even at low PO2: - stores as O2 -O2 reserve for muscles - Buffers O2 need onset of exercise until cardio pulmonary system increases O2 delivery

Both the right and left lungs are enclosed by a set of membranes called ___________.

pleura

pulmonary circuit

pumps DEoxygenated blood to the lungs from the RIGHT side of the heart and returns oxygenated blood to the LEFT

systemic circuit

pumps Oxygenated blood to the whole body from the LEFT side of the heart via arteries and returns DEoxygenated blood to the RIGHT side of the heart via the viens

cellular respiration

refers to O2 utilization and CO2 production by the tissues

pulmonary respiration

refers to ventilation(breathing) and the exchange of gasses (O2 and CO2) in the lungs

what are the structures of the respiratory zone?

respiratory bronchioles alveoli sacs

Input for the regulation of ventilation can come in the form of afferent pathways from Mechanoreceptors in the _________ of the heart relative to increases in cardiac output.

right ventricle

Blood flow within the lungs is uniform when an individual is in the __________ position.

supine

total lung capacity

the max amount of air(gas) in the lungs at the end of max inspiration

peripheral chemoreceptors

- Aortic and carotid bodies - sensitive to PO2, PCO2, H+, and K+ in blood

At the Tissues _____ PO2

- Low PO2 - releases O2 to tissues form deoxyhemoglobin

what sends the signal to neural input?

- Muscle mechanoreceptors (muscle spindles, Golgi tendon organs, joint pressure receptor. - Muscle chemoreceptors: sensitive to K+ and H+ concentrations