Joshua Post 7

Angiosperms are types of plants that have flower structures on them. Flowers are the special, delicate structures for reproduction. The reproduction of angiosperms is known as sexual. This is because they contain the male parts that make pollen and the female parts that make ovules. The male part is known as the stamen, which has something called an anther at the end of it. The female part is known as the pistil, which also has the stigma at the end of it. Angiosperms must go through a process known as pollination before they can reproduce. Angiosperm pollination can be self-pollination, where it pollinates itself, and cross-pollination, where a vector transports pollen from one plant which fertilizes another. During pollination, the pollen from the male part of the flower known as the anther has to be taken to the end of the female stigma. The stigma then carries the pollen down in a tube known as the style, so it can reach the ovary. Once the pollen reaches ovule, it can fertilize a female gamete. After the gamete has been fertilized, an embryo is formed and the growing ovule begins to grow into a seed. The seed is then dispersed in many different ways, ensuring the reproduction and survival of the plant species. 

Here, we see an intact Brassica Oleracea flower. None of the flowers parts have been ripped off of it yet and it remains as it would in the wild. Here, we can see the stamens and the anthers. Along with that we can see the petals of the flowers and the pistil, which is the female part of the flower. 

Here, we are seeing the plant under a dissection microscope. We clearly see the pistil and stigma, which are part of the female reproductive system. We also see the stamens and the anthers which are a part of the male reproductive system. When a plant has both the female and the male reproductive systems, it is known as perfect. In some species, they are on different flowers, and even on different plants. In this case,  the pollen would have to reach the female system by transportation through vectors or the wind.  In this photograph, the petals of this Brassica Oleracea have been completely removed to expose the reproductive systems. 

In this photograph, we are looking at the female reproductive sections of this plant. The stamens and anthers have been ripped off. We see the pistil, which has some visible pollen on the stigma. In reproduction, the pollen on the stigma would be taken down to the ovary through the style where it would fertilize a female gamete and form a seed. The pollen can adhere to the stigma, which is a way of catching pollen that is flying by fast in the wind. 

Here, we are looking at the male reproductive parts of the Brassica Oleracea. This part is made up of the stamens and the anthers. The anthers are the tiny things at the tip of the stamens that contain pollen on them. This pollen is the pollen that is used to fertilize the female gametes and form a seed. Often times, pollen has to be carried through vectors or by the wind to fertilize far flowers. This would be the case with cross-pollinating plants. Self-pollinating plants contain both male and female reproductive systems. 

This is a close up of pollen from the Brassica Oleracea that we have been looking at. We are seeing these particles under a compound light microscope under magnification 100x. These little particles are those that fertilize the female gametes which results in a seed. These seeds are then dispersed which ensures the reproduction and survival of the species. 

Joshua Post 6

Since the day we planted our plants, they have been growing. They have grown a lot since then, and that is due to various cellular processes. Those very important cellular processes are know as Mitosis, Photosynthesis, and Cellular Respiration. They all play a big role in the growth of our Cabbage plants in regards to biomass.

Mitosis is a very important process most animal and plant cells undergo. Before mitosis, our plants cells must go through interphase. First, the cells grow in size and build organelles. Then, the cells DNA is copied and microtubules form. The chromosomes, which is DNA wrapped up with histone proteins, are condensed during the first stage of mitosis, called prophase. During the third phase of mitosis, anaphase, the copies of chromosomes are pulled apart and each side of the parent cell has a copy of identical genetic information. During a process that comes after mitosis, called cytokinesis, a cell wall must form in between the new cells. This results in two daughter cells that result from the parent cell. This is the main way that our plant is adding biomass because the cells in our plants structures are undergoing mitosis every day. This results in more cells, which expands tissues, which results in more biomass. Our plants derive the energy to do this from ATP, a molecule made during photosynthesis and cellular respiration.

During photosynthesis, the chloroplast and chlorophyll in the plant cells take in solar energy, carbon dioxide, and water to convert to glucose and oxygen (6CO2 + 2H2O --> C6H12O2 + 6H2O). When light hits the plant, it excites the chlorphyll, which is a light absorbing pigment in the chlorplasts, and enzymes begin breaking apart water molecules. The hydrogen and oxygen molecules travel in a electron transport chain along the thylakoid membrane of the chloroplasts. NADPH is then created from NADP+, and ATP is also created through enzyme ATP synthase. These are the products of the light dependent reactions, meaning light energy was required to drive them. The light independent reactions build sugars using the ATP and NADPH made in the light dependent reactions. These help the plant grow in biomass because they provide energy for the cells to undergo mitosis. Cellular respiration also produces ATP.

In the process of cellular respiration, plants use the products of photosynthesis as the reactants. Cells use glucose and oxygen to yield carbon dioxide, water, and ATP (C6H12O2 + 6H20 --> CO2 + H2O + ATP).  The main idea of cellular respiration is to break down sugars into energy that the plant can use. Cellular respiration usually uses oxygen, and is called aerobic respiration. Cellular respiration however is not limited to only occuring when oxygen is present. When it takes place without oxygen, it is known as fermentation, but only glycolysis can happen. Cellular respiration has 4 stages; glycolysis, the Krebs cycle, link reaction, and electron transport chain. In glycolysis, glucose in the cytoplasm is broken down to two molecules of pyruvate. The pyruvate is broken down to produce acetyl-CoA in a process known as pyruvate oxidation. The Krebs cycle then uses this molecule to produce NADH, FADH2, ATP molecules, and carbon dioxide. The NADH and FADH2 will pass their electrons through the electron transport chain and the result will be ATP, through a process known as oxidative phosphorylation. As the electrons pass down this chain, energy is released and used to pump protons out of the mitochondrial matrix, which results in a gradient. The protons go back into the mitochondrial matrix through an enzyme known as ATP synthase, which makes ATP. The ATP is used for many reasons, but primarily for growth. Biomass is added from this growth.

The Production of enzymes depends mainly on two things, ribonucleic acid and ribosomes. To build enzymes, a mRNA copy has to be transcribed in the nucleus from DNA. RNA polymerase would transcribe the mRNA. The mRNA strand would then leave the nucleus and a ribosome would eventually attach itself to it. The ribosome would then start translating 3 nucleotides at a time, and would start at codons UAG, UGA, or UAA. The tRNA in the ribosome would attach an anti-codon to the mRNA codons and the oligopeptide, which in this case is an enzyme, would begin being assembled. One amino acid is translated from 3 nucleotides. This is how our plants would make enzymes if a message was sent to the nucleus that the production of certain enzymes was needed. After they enzyme is synthesized, it would have to travel to its destination. To do this, the enzyme would first pass through the endoplasmic reticulum. If the enzyme was needed somewhere outside of the cell, it would go to the golgi apparatus where it would be packaged in vesicles and sent to it's destination.

Karishma's Blog Post #6

After growing for six months, our plant has grown exponentially. The majority of the mass that the plants gained comes from carbon.  During the process of photosynthesis, plants also gain carbon dioxide. They take energy from the sun, water, and carbon dioxide. They use all these nutrients to convert into glucose and oxygen. When the sunlight hits the chloroplasts, it activates an enzyme that causes water molecules to break apart. Due to this, the hydrogen ions and free electrons convert NADP+ to NADPH which is used during light-independent reactions. During light-independent reactions, plants build up sugar from carbon dioxide and products from light-dependent reactions (ATP and NADPH) More glucose can also come from ATP since ATP assists the plants in making more glucose.

Plants also utilize cellular respiration. The plants obtain some of their carbon from animal cellular respiration. Animals take in oxygen and sugar that is made when plants undergo photosynthesis and convert it into carbon dioxide along with energy (ATP) and water. Cellular respiration occurs in the mitochondrion of the cell. During cellular respiration, plants fix carbon dioxide. They also break down sugar into usable energy for the cell (ATP). Cellular respiration occurs when light is scarce.

This all helps the plant grow in biomass. From both, cellular respiration and photosynthesis, plants can take in and use carbon dioxide that would contribute to the increase of biomass in plants. Additionally, plant cells divide (cell division). During cell division, the cell will start to duplicate the genetic material when chromosomes attach to each other to form sister chromosomes. During metaphase, these chromosomes will line up along the equator of the cell. In anaphase, the chromatids start to split apart and move to different poles. Afterward, the cell goes through telophase and cytokinesis. Here the two cells pinch together and two daughter cells are formed. This process of mitosis occurs millions of times inside one living organism. As an organism gains new cells, its mass would grow.

When the plant is in need, it can easily make necessary enzymes. Enzymes are a certain type of protein that catalyzed chemical reactions. Since enzymes are proteins, they are made in the same way as proteins. Therefore, it is the same exact process. Once the signal is sent to the nucleus that the cell is in need of the certain enzyme, the DNA code for that specific enzyme gets copied by RNA polymerase. The messenger RNA (mRNA) leaves the nucleus of the cell and enters the cytoplasm. Here it comes into contact with the ribosomes. The ribosomes attach to the RNA and read each codon (three nucleotide bases) in order to select the necessary amino acid. Additionally, tRNA attaches itself to each codon before it goes through the ribosomes in order to ensure the RNA to confirm it is choosing the correct amino acids.  Once the stop codon is reached in the RNA, the amino acid is formed and the amino acid goes on to construct the protein that the amino acid is being coded for. That is how enzymes would be made in the plant.