Umbilical cord

For loose connective tissue and smooth muscle fibres


Workbook tasks

Slide 100: Umbilical cord


This specimen is a cross section through the umbilical cord.

This is a cross section through the umbilical cord. The three large blood vessels are used as examples of smooth muscle.



  • The orientation of the three large blood vessels of the umbilical cord.


  • Longitudinally sectioned smooth muscle fibers.

  • Cross sectioned smooth muscle fibers.

  • In the tissue and between the blood vessels the following:

  • Fibroblasts

  • Collagen fibers

  • Amorphous ground substance


Draw and annotate:

The three components of gelatinous connective tissue in the correct ratio. Draw an additional fibroblast showing its microscopic detail (at higher magnification).

A few longitudinal and cross sectioned smooth muscle fibers. Note the shape and different diameters of the smooth muscle fibers.


  1. What is the shape of the fibroblasts and their nuclei? Compare this to the smooth muscle present in the blood vessel.
  2. How is the collagen arranged? Compare to irregular dense connective tissue.
  3. How do the collagen fibers appear? Compare to irregular dense connective tissue.
  4. How does the amorphous substance appear and how does it stain?
  5. What is characteristic of the cellular and nuclear shapes of smooth muscle fibres? Do all muscle fibres have the same diameter? Explain.
  6. How does the nucleus appear in a contracted smooth muscle fibre?
  7. What is found between the muscle fibers?



Cross section through the umbilical cord

© augustus 2019 marius loots