Observing Cells of the 5 Kingdoms PDF

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Summary

essay describing the cell theory and moving into more depth regarding the 5 kingdoms. Includes: Robert Hooke and Robert H Whittaker. 5 Kingdoms: Kingdom Animalia, Kingdom Plantae, Kingdom Fungi, Kingdom Protista and Kingdom Monera.
Includes a method practical: Examining a fungal cell in a rib...

Description

Observing Cells of the 5 Kingdoms Introduction The cell theory consists of three main principles. Firstly, it states that every single living system is made up of cells. Secondly, all cells come from preexisting cells through the process of cell division and thirdly, cells are the building blocks of life. As Sunghul Ji (2012, p.6) said, “we are cells, and cells are us”. The Cell Theory is a scientific understanding that describes physiological properties such as the structure, function and organelles of which cells contain. The term ‘cells’ was first used in 1665 by English Scientist Robert Hooke. He examined a section of cork under a compound microscope whereby he discovered tiny pores and empty structures enclosed by a wall. He published his discovery in his book called Micrographia. Hooke (1665, p.45) stated: “I could exceedingly plainly perceive it to be all perforated and porous, much like a honeycomb”. He came to call these ‘honeycomb’ like structures, cells. The name derived from the association between the tiny pores and the cells monks lived in. Despite his discovery being pinnacle to the introductory idea of cells, his method was very basic. As the National Geographic (2019) stated: “His microscope used three lenses and a stage light.” Hooke gave no indication of any organelles such as a nucleus present in a cell. In 1674, Anton Van Leeuwenhoek discovered the existence of single-cell organisms whilst observing algae spirogyra. In 1838-1839 Mattias Schleiden and Theodor Schwann furthered Hooke’s discovery of cells and discovered that most plant cells are made up of cells and recognised structures within plant cells such as a nucleus. They interpreted the importance of the nucleus and established cell division. In 1855, Rudolf Virchow determined all cells come from pre-existing cells. The discoveries made by these scientists, all contributed to the cell theory. In 1969, Robert H. Whittaker produced a system which categorised cells known as the five Kingdom System. The five groups are Kingdom Animalia, Kingdom Plantae, Kingdom Fungi, Kingdom Protista and Kingdom Monera. The first aim of this practical is to determine the basic structure of each of the cells in the 5 Kingdoms. The second aim is to learn the similarities and differences among these.

Method The practical is split into 5 parts. Each part will focus on observing each of the 5 Kingdoms. Part A consists of examining a fungal cell in a ribwort plantain. Firstly, remove fine roots from a ribwort plantain and wash with water to remove any soil particles present. Secondly, place the root in a boiling tube and pour 2.5% w/v Potassium Hydroxide (KOH) solution ensuring the root is covered. Thirdly, place the boiling tube in a fume cupboard, which will heat at just below boiling point, in a water bath for 25 minutes. Next, remove the boiling tube from the fume cupboard and allow this to cool for a few minutes. Once cooled, rinse the roots twice with distilled water to remove the hydroxide. After this, place the roots in 1% hydrochloric acid (HCI) solution to acidify them. Then, to stain the roots, put them in a 1% solution of Quink Permanent Blue ink for 5 minutes. After the time is up, wash the roots in 1% HCI to remove any excess stain solution and lay the root on a microscope slide. Use the pipette to

cover the root with a drop of glycerol and observe under a microscope. Once a fungal cell is observed, record via drawing what you see. Part B of the practical will consist of examining a bacterial cell in an active yoghurt. Firstly, spread a very thin layer of active yoghurt onto a microscope slide and cover this with a coverslip. Secondly, observe this under a microscope. Begin at magnification x10, working through until the specimen is being observed at magnification x400. Finally, remove the coverslip to and add a drop of immersion oil to the yoghurt. Place the coverslip back and observe this at x1000. The purpose of adding immersion oil is that it soaks the light path between the lens and yoghurt, therefore allowing finer details to be seen. Once a bacterial cell is observed, record via drawing what you see. Part C of the practical consists of examining a Protista cell in soil culture solution. Firstly, use a pipette to put a drop of soil culture solution on a microscope slide. Cover this with a coverslip. Secondly, observe this under a microscope beginning at x10 magnification, working through until focused at x400. What you will see are ciliated protozoa. These move very quickly so you will not be able to draw them. Therefore, once you have observed these, collect a prepared slide of Paramecium and place this under the microscope. Once focused at x400, record via drawing what you see. Part D of this practical consists of examining a plant cell in a moss leaf. Firstly, place a moss leaf on a microscope slide. Secondly, place a drop of water onto the specimen and cover with a coverslip. Thirdly, examine the cells under the microscope beginning at the lowest magnification x10 and working through until x1000 is reached. Once a plant cell is observed, record via drawing what you see. Part E of the practical is examining an animal cell in cheek epithelium. Firstly, collect a prepared slide of cheek epithelium cells and place it underneath the microscope. Observe this, beginning at the lowest magnification x10 and working until x1000. Once an animal cell is observed, record via drawing what you see. Results should be recorded after viewing each of the five cells. Results

Fungal Cell in a Ribwort Plantain

A bacterial cell in an active yoghurt

Protista cell in a Paraceium

Plant cell in a moss leaf

An animal cell in cheek epithelium

Discussion The purpose of my results is to show the structures and properties of individual cells within the five kingdoms. Looking at my results, this purpose has been met and clearly shows the structures and properties I observed underneath the microscope. The results I gained were to be expected. As previously been taught about the structures and organelles of cells, I was able to compare my findings to this which allowed me to view what I successfully observed and what I had overlooked. Kingdom Fungi can be single-celled or multicellular made up of threadlike hyphae. Their structure includes a cell wall made of polysaccharide chitin and organelles including a cell membrane, vacuole, mitochondria and endoplasmic reticulum. Although I observed all of the cell’s organelles apart from the endoplasmic reticulum, after looking at my results, it is possible I actually viewed this but did not notice at the time of observing the cell, underneath the microscope. In my opinion, on my diagram, I overlooked this as I am convinced the endoplasmic reticulum is underneath vacuole as it should be. Kingdom Monera are single-celled organisms and consist of the following within its structure: a cell wall made of peptidoglycan, hair-like projection named Pilli, flagella, a plasma membrane and small ribosomes of 70 svedberg units. The cell's DNA is free in the nucleoid region located in the cytoplasm. Comparing this to my findings, the only organelle I did not observe underneath the microscope was Pilli. Kingdom Protista are described as being diverse. Cells can be unicellular or multicellular and can possess flagella, cilia or an amoeboid mechanism for movement. A Paramecium cell contains the following within its structure: An anal pore, a food vacuole, lysosome, posterior and anterior contractile vacuole, gullet, a micronucleus, and a macronucleus. Comparing this

to my findings, I failed to observe lysosome, posterior and anterior contractile vacuole, and either of the two different nuclei. Kingdom Plantae are multicellular organisms. The structure of a plant cell includes a cell wall made from cellulose, cell membrane, a vacuole, chloroplasts, a nucleus, mitochondria, rough endoplasmic reticulum and smooth endoplasmic reticulum. Comparing this to my findings I didn’t see the rough or smooth endoplasmic reticulum. Kingdom Animalia are multicellular organisms and their structures include, a plasma cell membrane, lysosome, Golgi body, mitochondria, smooth and rough endoplasmic reticulum, nucleus and nucleoids. Comparing this to my findings, I didn’t observe the Golgi body. Cell biology as a whole is very important. From an upset stomach to a fatal disease such as meningitis are both due to problems being caused with your cells. By understanding how cells work in a healthy or diseased state, biologists are able to make further developments and improvements to prevent illnesses and control health in the future. In 1928, Alexander Flemming found Penicillin, in the Fungi Penicillium, to have a successful antibacterial response on pathogens. This is now used as worldwide and works “by killing bacteria or preventing them from spreading”, as stated by the NHS (2019). An example of how animal cells have aided in the development of cells was stated in the Standford website (2006): “Andrew Fire won a Nobel Prize for Physiology or Medicine for recognizing that certain RNA molecules can be used to turn off specific genes in animal cells.” Their discovery is now known as RNA interference (RNAi). Conducting this experiment, I found the microscope easy to use, thus making the observation of cells as a whole fairly simple. However, this being the first time viewing cells underneath a microscope and not being fully trained does come at a disadvantage. I found because of this, it took a while to thoroughly look to find and make out the organelles. Nevertheless, I found after repeatedly looking underneath the microscope, I gained more confidence in what was observing. A second difficulty, I found in the experiment was the amount of specimen required. Especially in regards to viewing the bacteria cell through active yoghurt. I did have to discard the first slide I put the yoghurt onto as the layer I applied was too thick. The problem with the yoghurt being too thick was that the cells were covered meaning I could not see them. However, because of this, it did make me more mindful on the amount I should be using and did eventually apply a very thin layer meaning I was able to view the cells successfully. The difficulties I experienced with this method, I would now stress as recommendations when repeating this experiment again. I would stress to ensure the correct amount of specimen is used as it can cause an effect on the findings. Due to the various organelles in each of the Kingdoms, there are many similarities and differences in each of them. The main difference being that they are either categorised as Eukaryotic or Prokaryotic. Prokaryotic cells are the simplest as they lack a distinct nucleus and organelles. Kingdom Monera (Bacteria) is an example of this. Eukaryotic cells are more complex as they contain a distinct nucleus and organelles. Kingdom Protista (paramecium and slime moulds), Fungi, (mushroom and yeast) Plantae (plants) and Animalia (animals) are examples of this. From my findings, it is clear to see this difference. The bacterial cell

diagram showed no distinct nucleus only a nucleoid whereas the other cells that are categorised underneath Prokaryotic all contained a nucleus. Conclusion The first aim of this practical is to determine the basic structure of each of the cells in the 5 Kingdoms. The second aim is to learn the similarities and differences among these. I can clearly observe a distinct structure of each of the cells within the five kingdoms which I have shown in my results. The second aim regarding the similarities and differences of the Kingdoms has been met as I was able to state the points I had noticed. To conclude, I am confident I have answered my aims and objectives.

REFERENCES Ji, S., 2012, Molecular Theory of the Living Cell. New York: Springer New York. Hooke, R., 1665, Micrographia. Great Britain: The Royal Society National Geographic., 2019. History of the Cell: Discovering the Cell. Washington: National Geographic. Available from: https://www.nationalgeographic.org/article/history-celldiscovering-cell/ . [Accessed 3rd April 2020]. NHS., 2019. Antibiotics. Available from: https://www.nhs.uk/conditions/antibiotics/ . [Accessed 30th March 2020]. Stanford Medicine., 2006. Andrew Fire shares Nobel Prize for discovering how doublestranded RNA can switch off genes. California: Krista Conger. Available from: http://med.stanford.edu/news/all-news/2006/10/andrew-fire-shares-nobel-prize-fordiscovering-how-double-stranded-rna-can-switch-off-genes.html . [Accessed 30th March 2020].

The relevant pages of my lab book are below....