biology unit 5 edexcel

how does the temperature receptor wrk for heart rate?
and hw to determine ventilation rate from volume of blood against time graph ?
and can anyonee help me by briefly typing procedures of investigating the effect of temp for rate or respiration in seeds by using respirometer pls? thnks

how does the temperature receptor wrk for heart rate?
During exercise ,the temperature receptors are the Chemo receptors found in in carotid bodies, , arteries and the medulla which detect the increase in the CO2 concentraion in the blood. They also detect the change in pH due to CO2 forming carbonic acid which dissociates producing low pH. These receptors then send the nerve impulses to the medulla oblongata. Then the medulla sends impulses back into the heart through the sympathetic nerve to increase the frequency of nerve impluse so the heart rate increases.
But when the CO2 concentration is less after exercise, the frequency of impulses is less so the heart rate decreases.

ohh so chemo receptors detect chnge in pH and temperature both? but temperature is mostly the environmental chnges right? like how warmer or cooler it gets? how is temperature related to CO2?

Chemo receptors dont detect temperature.
They actually detect the change in pH But it is better writing both as some mark schemes have only CO2
Temperature is not related to CO2 here

ohhh okhaay so temp receptors are chemo receptors found in heart?
so if there's a ques related to watever i asked shud i write abt hw chemo receptors wrk?

Chemo receptors are not Temp receptors