关于动物内环境稳态的叙述,错误的是( )①血浆渗透压与蛋白质含量有关,与无机离子含量无关 ②运动后Na+、K+排出体外较多,但机体的内环境仍维持相对稳定状态 ③抗原与抗体的特异性结合发生在内环境中 ④内环境成分中含有CO2、尿素、神经递质等⑤组织液渗回血浆和渗入淋巴的量相差较大 ⑥血浆的成分稳定时,机体达到稳态
A:①④⑤
B:②④⑥
C:①⑥
D:③⑤⑥
For our safety, we'd better avoid ____ (go) out alone at night.
–– Beijing is a big city, isn't it?
–– Yes. In fact, it's one of ________ cities in the world.