Obviously our plant has gotten substantially larger from the last time we looked at it. It doesn't magically just put out more and more mass. So what exactly does it do? Well each of the cells go through mitosis. Mitosis is where a cell divides and creates basically a replica of itself. A cell first goes through interphase where the cell duplicates its organelles and copies its DNA. DNA is a pretty important thing in cells because it is the structure for their life. The DNA is copied through a semi-conservative replication. The process involves a couple enzymes and it occurs in the nucleus. The helicase unwinds the double helix and the DNA polymerase adds new nucleotides and copies the DNA. Why it is semi-conservative is one strand is copied backwards and the other one is copied normal. This is the longest phase by far. After interphase prophase happens. Prophase consists of the chromosomes condensing and the nucleus disappearing. Microtubles are also formed. Next, metaphase begins. In metaphase the chromosomes line up and prepare to be split. Then, anaphasae occurs and the chromosomes move to opposite sides of the cell. Finally telophase takes place. The chromosomes reach opposite walls and the cell begins to divide. Cytokenisis finishes it off and there is 2 new cells. Seems like a lot just for growth, but there are tons of cells constantly at work doing this and growing the plan or repairing it. For example, our plant has lots of holes from bugs eating it away and the holes will slowly form again because mitosis is happening. Also at the tips of the leaves the plant will be growing as well.
How do the cells obtain the energy to do all this? Well what they do is photosynthesis. Photosynthesis allows cells to take sunlight and convert it into energy. This all occurs in the chloroplasts of the cells. Another way our plant was obtaining energy was through cellular respiration. Cellular respiration is a processes that take place in the cells of organisms to convert biochemical energy from nutrients into ATP. and then releases waste products. Respiration normally uses oxyegen and has 4 steps known as glycosis, link reaction, the krebs cycle, and electron transport train. In glycosis the glucose in the cytoplasm is broken down into 2 molecules. Next in the link reaction, pyruvate molecules are decarboxylated in the mitochondria. Pyruvate molecules are oxidized and converted to acetylcoenzyme A. In the krebs cycle, which takes place in the mitochondria, consumes oxygen and produces Co2 and ATP. The Co2 is released and the ATP is used in the cell. Well, that's how our plant was growing all this time.
Enzymes are a crucial part of any living organism's life. Plants use a vast amount of enzymes, but where do they get them? If a cell is told a specific enzyme is needed, then it will begin protein synthesis, because enzymes are proteins. Protein synthesis occurs in the nucleus and ribosomes. Before anything happens the cell must create mRNA. This is made during transcription when a copy of the DNA is created. The mRNA has 3 letter sequences on it that are codons and they are codes for amino acids. After the mRNA is made it is sent to the ribosomes to begin translation. Translation is where the ribosome reads each codon using an anticodon and creates the correct amino acid. Once it is complete you are left with a new protein which if was asked for would be an enzyme.
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