The higher the threshold, the higher the tissue excitability () A: The higher the excitability B: The lower the level of excitement C: The higher the level of excitement D: The less excitability E: No excitability

The most basic feature of life activities is A: substance metabolism B: energy metabolism C: metabolism D: excitability

Under normal circumstances, the effective stimulus to maintain the excitability of the respiratory center is increasing of CO2 partial pressure in arterial blood.

Under normal circumstances, the effective stimulus to maintain the excitability of the respiratory center is increasing of CO2 partial pressure in arterial blood. A: 正确 B: 错误