| MadSci Network: Botany |
Your observations should simply be what you observed. It would be very desirable for you to draw and label pictures of the intact carrot, a cross section and a longitudinal section. You might see shriveled remains of small lateral roots on the surface of the carrot taproot or storage root (Reference 1). You can place a carrot top in water and may get some lateral roots to form (Reference 2). Reference 3 notes the common misconception that a carrot storage root has an epidermis and cortex, like dicot primary root photos and drawings in textbooks. The carrot storage root has undergone lots of secondary growth. The cortex and epidermis have been destroyed due to this secondary growth, which caused a great increase in root diameter. The outer "skin" is termed the periderm. The inner vascular cylinder is mainly xylem. The bulk of the carrot root is secondary phloem containing a lot of parenchyma (Reference 4). If you cut a carrot longitudinally, you may be able to pull out the central cylinder and see lateral roots that extend out from the central cylinder (see next to last reference). If you have a microscope and some stains, you could stain the sections to help identify tissues and determine function (see the last reference). In this case, your conclusions would be more of a summary of what you learned. It would probably be desirable to relate structure to function. Also, it would be useful to include the carrot scientific name, Daucus carota. References Carrot drawing with remains of lateral roots Kid's Carrot Experiments Avoid Misconceptions When Teaching about Plants Description of carrot secondary growth in Introduction Carrot longitudinal section Root anatomy Carrot root dissection Root hair absorption
Try the links in the MadSci Library for more information on Botany.