The structure of sperm cells in mature trinucleate pollen grains of Beta vulgaris L. was studied with the electron microscope. The ellipsoidal sperm cell nuclei and cytoplasm are products of mitosis and cytokinesis of the ellipsoidal generative cell. Each sperm cell is separated from the vegetative...
tod1 is defective in in vivo pollen tube growth To investigate the cause of male sterility, mature pollen grains were stained with Alexander’s stain and with 4′,6-diamidino-2-phenylindole (DAPI) and analysed by microscopy. The cytoplasm of tod1 pollen was red purple after Alexander’s stai...
Pollen grains of Brassica campestris L. var. acephala DC and B. oleracea L. were serially sectioned and examined using transmission electron microscopy to
The two types of vacuoles co-exist in the same cells for a short time and may also be present in cells at different stages of development7–9. The complex fusion of PSV membranes and the changes in the vacuole content lead to the establishment of LVs10. In recent years, the origin of...
In such seeds, the cotyledons or first seed leaves become quite large and accumulate the reserves that will be mobilized later in germination. Reserves may take the form of intracellular oil droplets (for example, the sunflower), protein bodies (beans), and starch grains (cereals), or ...
This is a normal developmental process by which the WT anther produces mature pollen grains. However, in the ms33-6038 anther (right of Supplemental Figure 14D), loss of ZmMs33 function leads to greatly decreased contents of lipid components that are crucial to the integrity and function of ...
However, several transcripts, which encode proteins that are most similar to hypothetical Arabidopsis proteins, appeared to be present exclusively in the sperm cells inside mature pollen, but were already present in unicellular microspores. This suggests that certain transcripts might be transcribed early...
Mature pollen grains of a plant homozygous for the transposon insertion were able to germinate in vitro in a medium containing sucrose, glucose, or fructose, which indicates that PMT1 is not essential for pollen survival. Several explanations for these results are discussed in the present work....
In dicotyledonous plant, the first asymmetric zygotic division and subsequent several cell divisions are crucial for proembryo pattern formation and later embryo development. Arabinogalactan proteins (AGPs) are a family of extensively glycosylated cell surface proteins that are thought to have important rol...
Directly beneath the L1 lies the sub-epidermal L2 layer that generates the mesodermal tissues as well as the germ cells of the pollen grains and ovules. A third group of cells denoting L3 produces the stem vasculature and the innermost cells of the leaves and floral organs. Cells in the L1...