22.5 anatomy lec
Ventral Respiratory Group(VRG): Inspiratory area Displays __in impulse generation
autorhythmicity
Medullary Rhythmicity Area Controls the
basic rhythm of breathing
Contracting muscles consume large amounts of __ and produce large amounts of __
O2-consume CO2-produce
___ chemoreceptors - located in aortic arch and carotid bodies Detect changes in Pco2 , Po2 , and H+ in the blood
Peripheral chemoreceptors
TRUE OR FALSE- At the onset of exercise, there is an abrupt increase in pulmonary ventilation followed by a more *gradual* increase
True
Pontine Respiratory Centers Influence and modify activity of
VRG
dorsal respiratory groups DRG Integrates input from peripheral stretch and chemoreceptors; sends information -->
VRG
Active in sending impulses for 2 seconds (quiet inhalation) Inactive, no impulses, for 3 seconds (quiet exhalation) Cycle then repeats Sets eupnea (12-15 breaths/minute) Normal respiratory rate and rhythm.. describes?
VRG Inspiratory area
Expiratory neurons fire and inhibit inspiratory neurons leading to relaxation of muscles used for breathing (quiet exhalation)
VRG Expiratory area
Cortical influences allows for holding our
breath
abrupt changes from neural changes include Motor impulses from the __ __ cortex
primary motor
abrupt changes from neural changes include Sensory impulses from __ in muscles, tendons, and joints
proprioreceptors
Cortical influences allows for holding our breath this is a __ __
protective mechanism
Pontine Respiratory Centers Transmit impulses to VRG -->modify and fine-tune breathing rhythms during (3)
vocalization, sleep, exercise
Cortical influences allows for __alteration of breathing pattern
voluntary
Medullary Rhythmicity Area Consists of what 2 groups
ventral and dorsal respiratory groups
Other influences on respiration (7)
-Proprioreceptors -Inflation reflex Uses baroreceptors in the bronchi and bronchioles -Temperature -Pain -Stretching of the anal sphincter -Irritation of airways -Blood pressure
The more gradual increase in ventilation is due to; (3)
-Slightly decreased Po2 due to increased oxygen consumption -Slightly increased Pco2 due to increased carbon dioxide production by contracting muscle -Increased temperature due to increased metabolic activity of muscle tissue
Medullary Rhythmicity Area Located in the
medulla oblongata
Ventral Respiratory Group(VRG): Inspiratory area Thought to establish basic rhythm of __ __
quiet breathing
Cortical influences allows for holding our breath -Ability is limited by build up of__ and __ in the blood
CO2 and H+
___ chemoreceptors located near the medulla Detect changes in Pco2 and H+ in the cerebrospinal fluid
Central chemoreceptors
2 Chemoreceptors regulation of respiration
Central chemoreceptors Peripheral chemoreceptors
Cortical influences
Cerebral cortex has connections with the respiratory center
Hypothalamus and limbic system also stimulate respiratory center how?
Changes in breathing during laughing and crying
(Slightly increased Pco2 due to increased carbon dioxide production by contracting muscle) During high intensity exercise, HCO3- buffers excess H+ released from lactic acid -->more __formation--> more conversion to CO2 which further increases Pco2 Lactate threshold and anaerobic threshold, in part, depend on this system
H2CO3
(Slightly increased Pco2 due to increased carbon dioxide production by contracting muscle) During high intensity exercise, __- buffers excess H+ released from lactic acid -->more H2CO3 formation--> more conversion to CO2 which further increases Pco2 Lactate threshold and anaerobic threshold, in part, depend on this system
HCO3
2 subdivsions of respiratory center
Medullary rhythmicity area Pontine respiratory centers
__ __ : Responsible for control of pulmonary respiration and ventilation
Respiratory Center
Generation of the Respiratory, Most widely accepted hypothesis: Reciprocal inhibition of two sets of interconnected pacemaker neurons in medulla that generate rhythm of breathing MEANING
When one set fires, the other is inhibited
Cortical influences allows for holding our breath If one passes out from holding their breath for too long, breathing resumes when __is lost
consciousness
Decreases in arterial and CSF Pco2 , H+, and increases in arterial Po2 -->
decrease in breathing rate and depth Decrease offloading of CO2 and oxygen loading
TRUE OR FALSE- At the end of exercise, there is an abrupt increase in pulmonary ventilation followed by a more gradual decline to resting level
false
Chemoreceptor regulation of respiration is not a ___ system, why?
foolproof Severe deficits in O2 can cause respiratory depression causing a positive feedback cycle that can lead to death
Ventral Respiratory Group(VRG): Inspiratory area Active in sending impulses for how many seconds
for 2 seconds (quiet inhalation)
Ventral Respiratory Group(VRG): Inspiratory area Inactive, no impulses, for
for 3 seconds (quiet exhalation)
what type of exercise is this-Frequency and depth increase
high intensity exercise
respiratory center : Clusters of neurons located where?
in the medulla oblongata and pons of the brain stem
Increases in arterial and CSF Pco2 , H+, and decreases in arterial Po2 -->
increase in breathing rate and depth Offload more CO2, Load more oxygen
Pulmonary Adaptation to Exercise: CO increases, pulmonary perfusion __
increases
__ reflex Uses baroreceptors in the bronchi and bronchioles
inflation
VRG Expiratory area Expiratory neurons fire and __ inspiratory neurons leading to __ of muscles used for breathing (quiet exhalation)
inhibit relaxation
The basic rhythm of respiration set and coordinated by the VRG inspiratory area and can be modified by
inputs from other brain regions, peripheral receptors, and other factors
Pontine Respiratory Centers Smooth out transition between __ and __ & vice versa
inspiration and expiration
Ventral Respiratory Group(VRG)
inspiratory and expiratory areas
The respiratory and cardiovascular system makes adjustments in response to both __ & __ of exercise
intensity and duration
in exercise, Breathing rhythm and depth depend on the __ of __
intensity of activity
Generation of the Respiratory Rhythm has 1 hypothesis : Pacemaker neurons with __ __set the breathing rate
intrinsic autorhythmicity
(Slightly increased Pco2 due to increased carbon dioxide production by contracting muscle) During high intensity exercise, HCO3- buffers excess H+ released from lactic acid -->more H2CO3 formation--> more conversion to CO2 which further increases Pco2 __ threshold and __ threshold, in part, depend on this system
lactate and anaerobic
(Slightly increased Pco2 due to increased carbon dioxide production by contracting muscle) During high intensity exercise, HCO3- buffers excess H+ released from __ __-->more H2CO3 formation--> more conversion to CO2 which further increases Pco2 Lactate threshold and anaerobic threshold, in part, depend on this system
lactic acid
abrupt changes from neural changes include -Stimulation of the __system by anticipation of activity
limbic
Cortical influences allows for holding our breath Ability is limited by build up of CO2 and H+ in the blood When these concentrations become to great, voluntary control is__ and ..?
lost and breathing begins again
what type of exercise is this- Increased ventilation mostly due to increase in breathing depth rather than rate
moderate exercise
Chemoreceptors participate in a__ __system that responds to changes in homeostasis
negative feedback
At the end of exercise, there is an abrupt decrease in pulmonary ventilation followed by a more gradual decline to resting level Initial decrease due to __ __
neural input
In addition, the rate at which O2 can diffuse into the blood can increase up to 3x during maximal exercise because the pulmonary capillaries become maximally __ This results in the equivalent of a greater surface area available for diffusion of O2 into the blood
perfused
dorsal respiratory groups DRG Integrates input from __ __ & __ ; sends information -->VRG
peripheral stretch and chemoreceptors
Generation of the Respiratory Rhythm has 1 hypothesis : Pacemaker neurons with intrinsic autorhythmicity set
the breathing rate
Ventral Respiratory Group(VRG): Inspiratory area Sends impulses to what 2 areas
the external intercostals and diaphragm
TRUE OR FALSE- Abrupt changes are due to neural changes that excite the inspiratory area
true
TRUE OR FALSE- At the end of exercise, there is an abrupt decrease in pulmonary ventilation followed by a more gradual decline to resting level
true
TRUE OR FALSE- the heart pumps out the same amount of blood to the lungs as it does to systemic circulation
true
Generation of the Respiratory Rhythm is not well
understood