When observing muscle tissue under the microscope, what distinguishing feature can be found in cardiac muscle, but NOT skeletal muscle?

Cardiac muscle is only found in heart and skeletal muscle is found attached to bones.

When observing muscle tissue under microscope, different features found in   cardiac muscle, but not in skeletal muscle are as follows:

name and explain one of the event that occurs during meiosis that increases the variation in offspring even more than simple reproduction?

he forelimbs below belong to four species that descended in a direct line from the ancestral mammal shown above. of the four descendants shown, which species most likely appeared earliest in evolutionary history?