7. Cardiac muscle - alizarin blue and metanil yellow.
This is the slide in your box. At a first glance not very helpful isn't it? The yellow streaks are blood capillaries. Can you make out the large nuclei of the muscle cells? Intercalated discs are seen running almost vertically.

8. Does this help? In this picture (40x) from a H&E stained section, a single cell is outlined. See the single, central nuscleus. Note the branching of the cell at its left end. At both ends, even in the smaller branch, notice the thick intercalated disc.
True, striations are not seen well, but that is usually so in cardiac muscle.

9. This section, stained with iron haematoxylin, brings out the striations well. Can you see the branching and the single nuclei? Not in the student box.

10. Cardiac muscle in t.s. Again shrinkage is our friend! Note the single cell in the oval with its central nucleus.
Since cardiac muscle cells have single nuclei and they are not aligned in one plane, few cells show nuclei.