Cardiac output is defined as:

The protective membrane surrounding the heart is called .........

During ventricular systole,

Heartbeat can be initiated by

When the heart of a frog is removed from the body,it continues to beat for some time. Select the correct statement$(s)$ from the following:
$(i)$ The frog is a cold-blooded animal.
$(ii)$ The frog does not have a heart-based circulatory system.
$(iii)$ The heart has myogenic properties.
$(iv)$ The heart is self-excitable.

Blood pressure in the mammalian aorta is maximum during