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