Question

Explain in detail the negative feedback mechanism that was occurring in your body that lead to you needing to finally take a breath after having held your breath. Include the stimulus, sensor, afferent path, integrating center, efferent path, effector and response. Please and thankyou!

Answer 1

Homeostasis is a process of maintaining a normal internal environment of the body (for example; normal BP, normal temperature, normal respiratory and breathing rate, etc. There is two feedback system that helps in maintaining homeostasis. Negative feedback system and a positive feedback system

Negative feedback system: It reverses any changes from homeostasis. That means if anything deviates from the normal value ( for example BP deviated from the normal), the negative feedback bring that changes to the normal ( for example BP deviated from the normal, hypotension or hypertension, the negative feedback bring that changes to the normal BP)

Negative feedback occurs through a loop called a negative feedback loop. The components of the loop include

Stimulus: It is any changes from normal physiology (deviation from homeostasis)

Sensor: Mainly receptors and it is the part of a sensory neuron that detects that changes

Afferent path: It is the axon of the sensory neuron that coney the information from the sensor to the integrating center in the CNS

Integrating center: It a part of CNS where the sensory neuron synapses with interneuron and motor neurons. Integrating center process the information that is received from the Sensor

Efferent path: It is the axon of motor neurons. Processed information from the CNS is traveled to the effector through the efferent path

Effector: It is an end-organ that produces the effect. That may be muscle, gland, or organs, etc.

Response: It is the action produced by effector organ

Negative feedback in respiratory regulation

When you hold your breath, PCO2, and/ H+ concentration in the blood increases than the normal, and PO2 in the blood decreases than the normal. These deviations in PCO2, H+ (pH), and PO2 from the normal act as Stimuli (Singular: Stimulus)

Central and peripheral chemoreceptors such as carotid bodies and aortic bodies detect that changes in PCO2, H+ (pH), and PO2. So, chemoreceptors act as Sensor

Chemoreceptors convey in the information ( changes in PCO2, H+ (pH), and PO2) to the respiratory centers such as pontine respiratory groups (PRG), dorsal respiratory groups (DRG) and ventral respiratory groups (VRG)in the pons and medulla oblongata through glossopharyngeal nerve (CN IX) and vagus nerve (CN X). Here, the glossopharyngeal nerve (CN IX) and vagus nerve (CN X) are the afferent paths and respiratory centers are integrating center- Now the respiratory centers are stimulated

Integrating center (Respiratory centers) process the information and this processed information send to the diaphragm and intercostal muscle and causes hyperventilation. Here diaphragm and intercostal muscles are effector and hyperventilation is the response- Hyperventilation result in exhaling more CO2 and inhaing more O2 leads normal PCO2, PO2 and pH in the blood