Saba Mebrahtu

Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Biology and Microbiology


This research is a study of a morphogenetic shift of the soybean shoot apex from quiescence to germination. The minute changes in the organelles were recorded with the use of stereological methods. The ultrastructural data was statistically analyzed. The ultimate goal was the recognition of relationships between the cell's functional units and its structural units, with the identification of morphogenetic regulation mechanisms. Morphometric image analysis of cellular organelles indicated that storage reserves were transformed from lipid bodies to plastid starch. Proplastids and promitochondria, so difficult to differentiate in early stages of germination became obvious by 96 hours post germination. Significant differences were found in mean organellar volume fraction percent with reference to time at the four stages of development studied. The Waller-Duncan K-ratio T-test for organellar volume fraction percent by development time were significantly different in the 48 and 96 hour groups. Relationships between development time and each of the seven organelles studied were developed using regression. Cyclic fluctuations were observed in volume fraction percents of plastids, vacuoles and nuclei. A sharp rise in starch and sharp drop in lipid was observed. No change was observed in mitochondria and cell walls.

Library of Congress Subject Headings

Cells -- Morphology
Plant cell culture



Number of Pages



South Dakota State University


No Copyright - United State