Kin 391 - Ch. 10 Respiration

The ideal ventilation-to-perfusion (V/Q) is ___ or slightly greater.

1.0

Identify a structure that is part of the respiratory zone of the respiratory system

Alveolar sacs

a decrease in blood pH results in a right shift in the oxyhemoglobin curve and is called the ___.

Bohr effect

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

Circulatory transport

The total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert independently. This law of partial pressure is referred to as ___.

Dalton's law

T or F: arterial PO2 decreases and arterial PCO2 tends to increase slightly in the transition from rest to steady-state exercise. This observation suggests that the increase in metabolism at the beginning of exercise is not as rapid as the increase in alveolar ventilation

False - The increase in alveolar ventilation at the beginning of exercise is not as rapid as the increase in metabolism.

T or F: Analogous to the muscular-skeletal system and the cardiovascular system, the lungs also undergo adaptive changes in response to regular endurance exercise.

Flase - Endurance exercise training has no measurable effect on the lung structure and pulmonary function.

Systemic Gas Exchange

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

Alveolar Gas Exchange

It is the movement of respiratory gases between the gas exchange region of the lung and the blood.

cellular respiration

It refers to O2 utilization and CO2 production by the tissues.

Pulmonary respiration

It refers to ventilation (breathing) and the exchange of gases (O2 and CO2) in the lungs.

Peripheral chemoreceptors

Located in the aortic arch and at the bifurcation of the common carotid artery. The respond to changes in arterial H+ concentrations, PCO2 blood potassium levels, and arterial PO2.

central chemoreceptors

Located in the medulla and are affected by changes in PCO2 and H+ of the cerebrospinal fluid.

Diffusion limitations during intense exercise in elite athletes could occur due to a reduced amount of time that ___ spend in the pulmonary capillary.

RBCs

Ventilation

Refers to the mechanical process of moving air into and out of the lungs

vital capacity

The maximum amount of gas that can be expired after a maximum inspiration

In the oxygen-hemoglobin dissociation curve, identify the factors that determine the direction of loading and unloading reactions.

The partial pressure of O2 in blood, and the affinity or bond strength between hemoglobin and O2

In the context of the respiratory control center, identify the clusters of neurons that constitute rhythm-generating centers in the pons.

The pneumotaxis center and the caudal pons

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

The pons and the medulla oblongata

Diffusion

The random movement of molecules from an area of high concentration to an area of lower concentration

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

The total surface area available in the lung for diffusion is large and the alveolar membrane in the lung is extremely thin.

total lung capacity

The volume of gas in the lungs after a maximal inspiration

residual volume

The volume of gas remaining in the lungs after a maximum expiration

Aortic bodies

They are capable of sensing changes in blood levels of CO2 indirectly.

Carotid Bodies

They are sensitive to increases in blood potassium levels.

Identify a structure in the conducting zone of the human respiratory system

Trachea

T or F: the ventilatory threshold (Tvent) occufrs in both trianed athletes and untrained students.

True

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

a pressure difference between the ends of the passageway.

Heavy exercise results in ___.

a small V/Q inequality

the function of the respiratory zone is to ___.

act as the sit of gas exchange between the alveoli and blood

neural input to the respiratory control center refers to ___ input.

afferent or efferent

Airflow through the pulmonary system is increased anytime there is a decrease in ___.

airway resistance

The volume of inspired gas that reaches the respiratory zone is referred to as ___.

alveolar ventilation

The human respiratory system is composed of a group of passages that filter air and transport it into the lungs, where gas exchange occurs within tiny air sacs called ___.

alveoli

light-to-moderate exercise results in ___.

an improvement in the V/Q relationship

Although there is an increase in ventilation during prolonged submaximal exercise in a hot or humid environment, there is little change in PCO2. This suggests that the increase in ventilation is due to an increase in ___.

breathing frequency and dead-space ventilation

Movement of air from the environment to the lungs is called pulmonary ventilation and occurs via a 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

The most important variable contributing to airway resistance is the ___.

diameter of the airway.

The major muscle of inspiration, which causes an increase in the volume of the chest, is the ___.

diaphragm

In the context of the effect of 2-3 DPG (2-3 diphosphoglycerate) on the oxygen-hemoglobin dissociation curve, red blood cell concentration of 2-3 DPG increase ___.

during exposure to altitude

The conducting zone of the respiratory system not only serves as a passageway for air, but also functions to ___.

filter, warm, and humidify the air.

Approximately 99% of the O2 transported in the blood is chemically bound to ___.

hemoglobin

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

high-intensity

Fine-tuning of breathing to match the metabolic rate is performed by input from ___.

humoral chemoreceptors

A secondary factor that might contribute to ventilatory control during heavy exercise is a(n) ___

increase in blood potassium levels.

at the beginning of constant-load submaximal exercise, there is an initial rapid ___.

increase in ventilation

At a constant pH, the affinity of hemoglobin for O2 is ___.

inversely related to blood temperature

Blood flow within the lung is higher at the apex of the lung than the base of the lung when an individual ___.

is suspended upside down

When compared to the systemic circuit, the pulmonary circuit has a ___.

lower pressure

motor neuron activity is directly controlled by the respiratory control center in the ___.

medulla oblongata

Input for the regulation of ventilation can come in the form of efferent input from the ___.

motor cortex

oxygen transport in muscle is carried out by the oxygen-binding protein called ___.

myoglobin

Input to the respiratory control center can be classified into ___.

neural and humoral

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

pH

The acid-base balance is altered when a reduction in pulmonary ventilation results in a decrease in ___.

pH

Carotid bodies also promote increase in ventilation as a response to increase in blood levels of ___.

potassium

The primary purpose of the respiratory system is to ___.

provide a means of gas exchange between the external environment and the body

During active expiration, the muscles in the abdominal wall work to ___.

push the diaphragm upward

At rest, the process of expiration ___.

requires no muscular effort

research confirms that during high-intensity exercise, ___.

respiratory muscle fatigue does occur

contraction and relaxation of the respiratory muscles are directly controlled by ___.

somatic motor neurons in the spinal cord.

The technique used for measuring pulmonary volumes in the human body is known as ___.

spirometry

identify a technique used to measure pulmonary volumes in which a subject is required to breathe into a device that is capable of measuring inspired and expired gas volumes.

spirometry

The adaptability of pulmonary structures to endurance training is substantially less than the muscular-skeletal system and the cardiovascular system, because the ___.

structural capacity of the normal lung is overbuilt.

The amount of gas moved per breath is called ___.

tidal volume

What process occurs during the exchange of o2 and CO2 between the lung and blood?

ventilation and diffusion

Exercise-induced hypoxemia in elite athletes is likely to occur because of ___.

ventilation-perfusion mismatch and diffusion limitations.

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

ventilatory threshold