Which of the following best describes a closed circulatory system?单项选择题

A
a. A circulatory system where blood is pumped by a centralized heart and confined to vessels
B
b. A circulatory system where blood is not confined to vessels and bathes the tissues directly
C
c. A circulatory system where blood is confined to vessels and flows under constant high pressure
D
d. A circulatory system where blood is pumped by multiple hearts and flows through a series of chambers
登录即可查看完整答案
我们收录了全球超50000道真实原题与详细解析,现在登录,立即获得答案。
更多留学生实用工具
希望你的学习变得更简单
加入我们,立即解锁 海量真题 与 独家解析,让复习快人一步!