Blogpost #7 - Sam Albert

Dissecting Microscopes

Our Brassica oleracea plants are angiosperms, or plants that flower and produce seeds. The first 

step in fertilization is pollination, where pollen, moved by air or water, lands on the pistil of the flowers.

Soon after, the pollen grain grows a tube-like structure toward the egg cells in the ovary. The pollen then makes an opening in the ovules (a micropyle). The last step involved is the fertilization itself, where most angiosperms like our Brassica oleracea undergo double fertilization. In double fertilization, 

not only the zygote is made, but two polar nuclei are also made, which later goes on to make the 

endosperm, the food storage for the growing embryo. A seed starts to develop once the fertilization 

stage is over.

This first picture shows the female reproductive structure (carpel) of one of the Brassica oleracea flowers. The little green, pea-like structures are ovules, contained in ovary. The other structures shown are the stigma and style. The ovules can be viewed like this by cutting the ovary open with a fingernail. 

    In this image, the filaments and ovary can be seen. The filaments are part of the male reproductive structure in the angiosperm flowers. The sepals are mostly torn off to better show the other parts. Filaments are for holding up the anthers (the top part of the stamen).

This picture shows the stigma and the anthers. They're the main parts of the stamen and pistil, the male and female reproductive structures. The stigma takes in the pollen during fertilization, while the anthers control the pollen grains, containing the sperm cells.

This last image depicts the entirety of the flower we dissected. It falls under the category of a perfect flower, or one that has both male and female reproductive systems. This one has petals, a pistil, and anthers.