Cardiac muscle (longitudinal section)


Workbook tasks

Slide 20: Heart muscle


This is a longitudinal section through heart muscle. To view the cross striations the condenser of the microscope must be turn downward to produce contrast.

Identify microscopically:

  1. Muscle fibers and branchings
  2. Nuclei of the heart muscle fibers and connective tissue

  3. Intercalary discs and cross striations

  4. Connective tissue

Draw and annotate:

A heart muscle fibre. Indicate the characteristic components in detail.


  1. What is characteristic of heart muscle fibers?
  2. How do heart muscle fibers differ from skeletal and smooth muscle?
  3. What is the connective tissue found between the heart muscle fibers called?


Longitudinal section of cardiac muscle

Cardiac muscle

High magnification of heart muscle: normal contrast
High magnification of heart muscle: high contrast


© januarie 2008 marius loots