The Seeds of Life

Life is very fascinating. We owe our very existence to groups of atoms known as amino acids. They are what make up the structures and shapes of the proteins in our bodies that make every organism unique in their own way. Amino acids came before DNA (deoxyribonucleic acid) and have created the vast quantity of life that has inhabited Earth. There are only 20 amino acids that exist on Earth and together they have created thousands of proteins that living organisms use to perform many biological functions in their bodies. Although amino acids came before DNA, they are constructed by DNA in living organisms. DNA is kind of like a code that orders ribosomes to construct chains of amino acids that form proteins. They twist and fold over each other and their unique shape is what really gives them their purpose. They act like a "key in a lock" . The protein molecules fit into other proteins by having an exact shape that allows them to fit snuggly together.

Fast forward to the origin of vascular plants that reproduce with seeds. Angiosperms came into existence roughly 140 million years ago. What makes angiosperms unique is that they produce flowers and fruits. These parts of an angiosperm allow them to reproduce. The fruits are what protect the seeds and the flowers are what spread the pollen. These are important topics to learn about if you want to have a beautiful garden that keeps on giving.

I was lucky enough to have been recently gifted some cannabis seeds from one of my coworkers. He didn't give me a large quantity of seeds, but if odds work in my favor and I provide a suitable environment for them to grow, I can turn this small quantity of seeds into a large quantity of seeds. To make this happen, it is important to understand angiosperms. Cannabis are primarily known to be incomplete angiosperms, meaning, they don't produce female and male gametophytes in one plant. Although female cannabis plants can be hermaphroditic, they mostly only do that if they are stressed. So how do they reproduce? On male cannabis plants, there are microsporophyll known as stamen. On the tips of the stamen are anthers. Inside the anthers are microsporangium that contain diploid microsporocytes that divide by meiosis. Not to be confused with mitosis, meiosis is when a diploid cell divides its pair of duplicated homologous chromosomes into haploid cells. When the microsporocytes undergo meiosis, they become haploid cells known as microspores (pollen). Female plants have megasporophyll known as carpels. The carpel is made of a stigma, style and the ovary. Inside the ovary are ovules containing megasporangium. Inside the megasporangium of each ovule, there are megasporocytes that are also diploid cells and divide by meiosis. The cellular division creates haploid megaspores that form into individual parts of a female gametophyte. Pollination occurs when the microspore reaches the ovules and forms a zygote with the megaspore. An embryo forms and food is stored inside a seed that is created and protected by the fruit or what everyone calls the bud. This isn't even going into the molecular level of how the various proteins and enzymes interact during pollination and fertilization!

Here is a picture to help simplify what was just discussed. My illustration skills are very amateur but pay close attention to where the arrows and dashes are pointing in the picture. Also this is an illustration of a complete angiosperm, meaning, it has both male and female gametophytes.

A cannabis diploid cell has 20 chromosomes. A diploid cell is a cell that has all homologous chromosomes in its nucleus. When a diploid cell undergoes meiosis, its homologous chromosomes duplicate and separate. The duplicated chromosomes that are still attached to each other divide once again forming four haploid cells that each contain 10 chromosomes. The haploid cells are gametophytes and are what actively engage in pollination and fertilization.

Why is this important? It's important because it allows genetic variation. Fertilization of the two separate gametophytes allows desirable alleles to be combined and carried on in future generations. This is what breeds new strains of high quality cannabis. If a female plant were to turn into a hermaphrodite, it would pollinate itself and its genetics would not advance. Also if a female plant were to turn into a hermaphrodite, it is usually because the plant is stressed and in poor health. The stress causes the plant to resort to a last ditch effort to reproduce and unfortunately, produces poor quality fruits.

With the seeds that I recently acquired, I'm hoping that at least one of them is a male. A male plant would offer genetic variation and pollen that would grow a large quantity of seeds by pollenating a future generation. There is also a chance that the seeds that I have were pollinated by feminized pollen, which is pollen only containing X chromosomes. There are chemical tests to determine what sex chromosomes they have, but that involves killing the seed and extracting its DNA. I can't simply take samples of the seed's shell because the shell is made from female gametophytes and are not what produce the actual plant. The embryo inside the seed is what is needed and there is no conventional way to extract it without killing the embryo. I simply do not have enough seeds to perform those tests. The only way to know for sure is to start growing.