Week 4 - Cell Theory

This week the Topic that I learned is about Cell Theory and Prokaryote. We are given a task to be done before the class on the scientist that had contribute to the cell theory. There are 4 main scientist that had contributed to cell theory. I really look up to them, because without them, we will not be able to differentiate the different type of organism. We wouldn't know what made up of the organism, what causes the illness, how the system and things work in our body. The first scientist is Robert Hooke, he discovered the word 'cell', he examined thin slices of cork and discovered empty spores contained by walls. Next we learn about Anton Van Leeuwenhoek who upgraded the magnification of the microscope from  20x-30x to capacity of 270x. With this great invention we can examined many microorganism that cannot see by our naked eyes under the microscope. Besides he also discovered "animacules". This is the new word that I learned which is little animals for example amoeba. Besides Anton Van Leeuwenhoek also discovered bacteria from a sample of saliva from his mouth in the year of 1683. The 3rd scientist that I had look upon is Theodor Schwann, I remember this guy from my STPM text book, where he discovered the Schwann cells in peripheral nervous system. He came out with a cell theory that cells are organism and all organisms consist of one or more cells or cell is the basic structure for all organism. The last scientist is Rudoplh Virchow, where he came out with the cell theory stating that all living things come from other living things, the origin of cells was the division of pre-existing cells.

Besides I learn about the 3 traditional cell theory :
1. All living things are made up of cells.
2. All living cells come from pre-existing cells.
3. Cell is the basic unit of life.
And there is 3 modern cell theory:
1. Studies of biochemistry and metabolism proves that energy flow occur within all cells.
2. Cells contain hereditary information (DNA) that is passed from one cell to another cell during cell reproduction.
3. All cells are basically same in chemical composition and metabolic activities in organisms of similar species.

We also learn about prokaryotes and eukaryotes, stating down the similarities and differences. This is something that I had learned so is not something special to me. But I am quite interested with the next sub-topic which is viruses, prions and viroids. These are exception of cell theory, because they cannot be consider as a living things, they are not the basic unit of life but they can spread, attack and function like it is a living things. Besides viruses, prions and viroids, subcellular organelles such as mitochondria and multinucleated cells such as muscle cells are also exception of cell theory.

I think viruses, prions and viroids is very interesting, they are such a small molecule or organism, but they can do a lot of harm to humans, animal and also plant. This topic is also new to me. Viruses carries genetic material in protein that are called virus code where they code for protein that contain virus and spread to the all part of the body. Attacking the original or normal cell in the body by using the process Lytic cycle and Lysogeny cycle. Where as prions are infectious protein that will infect the normal prion protein by changing it shapes and conformation. This will lead to abnormal protein that will clogged and causes diseases such as mad cow. The next one is viroids which infect plants. Viroids causes the plants to have abnormal shapes. For example potato plants that is affected by viroids produced potato that is small and long. This will cause a big loss to the farmer that brings down the economy.

I enjoy the topic on the virus and prions. Maybe I'll consider myself in taking virology. If I were to do the class again, I'll nicely write down the points on lecture, and write a notes to myself after the class ended. This will help me remember better on the topic.

Mers Virus