Answer:
when Griffith was experimenting with pneumonia-causing bacteria he discovered that when two cultures were mixed, somehow the harmless bacteria changed, and that organism contained information that could be passed on to another organism.
and the phenomenon is stated right there in the answer
~batmans wife dun dun dun...
This question seem to be incomplete... Here is the full question
What causes the respiratory center in the medulla oblongata of the brain to increase the rate of respirations?
Answer:
decreased amount of oxygen or increased amounts of carbon dioxide in the blood
Explanation:
The medulla oblongata and the pons are involved in the regulation of the ventilatory pattern of respiration.
The decrease in blood pH result from the decreased amount of oxygen, Hypoxemia refers to insufficient oxygen in the blood. Thus any cause that influences the rate or volume of air entering the lungs (ventilation) or any cause that influences the transfer of air from the lungs to the blood may cause hypoxemia.
In response to a decrease in blood pH, the respiratory center (in the medulla ) sends nervous impulses to the external intercostal muscles and the diaphragm, to increase the breathing rate and the volume of the lungs during inhalation.
Also, Let take a look at a situation of an individual suffering from an anxiety attack(i.e hyperventilating). The increased ventilation rate will remove too much carbon dioxide from their body, (this implies that there is increased amounts of carbon dioxide in the blood). Without that carbon dioxide, there will be less carbonic acid in blood, so the concentration of hydrogen ions decreases and the pH of the blood rises.
In response, the respiratory chemoreceptors detect this change, and send a signal to the medulla, which signals the respiratory muscles to decrease the ventilation rate so carbon dioxide levels and pH can return to normal levels.
