Modern Observations on the Importance of Cells
The English scientist Robert Hooke who used a makeshift microscope of his own invention to examine a variety of objects, including a thin piece of cork, made the first observations of cells in 1665. Noticing the rows of little boxes that made up the dead wood's tissue, Hooke created the term "cell" because the boxes reminded him of the small cells the monks in the monastery lived in. While Hooke was the first to study and describe cells, he did not realize their importance. At about the same time, the Dutch maker of microscopes Antoni van Leeuwenhoek prepared for the invention of one of the best microscopes of the time. Using his invention, Leeuwenhoek was the first to study, draw, and describe a lot of living organisms, including bacteria in saliva, one-celled organisms in pond water, and sperm. Two centuries passed, however, before scientists understood the true importance of cells.
Modern ideas about cells appeared in the 1800s, when better light microscopes allowed scientists to observe more details of cells. Working together, the German botanist Matthias Jakob Shleiden and the German zoologist Theodor Schwann recognized the basic likeness between plant and animal cells. In 1839, they planned the new idea that all living things are made up of cells.
During the 1800s, scientists began to understand some of the chemical processes in cells.
In the 1920s, the ultracentrifuge was developed. The ultracentrifuge is a tool that spins cells or other things in test tubes at high speeds, which causes the heavier parts of the substance to fall to the bottom of the test tube. This device allowed scientists to separate the fairly heavy mitochondria from the rest of the cell and study their chemical reactions. By the late 1940s, scientists were able to explain the role of mitochondria in the cell. Using refined techniques with the ultracentrifuge, scientists subsequently isolated the smaller organelles and gained an understanding of their functions.
While some scientists were studying the functions of cells, others were examining details of their structure. They were aided by a crucial technological development in the 1940s: the invention of the electron microscope, which uses high-energy electrons instead of light waves to view specimens.
The Lives of a Cell: Notes of a Biology Watcher by Lewis Thomas consists of short, insightful essays that offer the reader a different perspective on the world and on ourselves.
Mitochondria are sub-cellular organelles which are found suspended in the cytoplasm of majority of eukaryotic cells. One of their functions is to produce energy in a form (ATP) that is useful for all cells to maintain the intra and extra cellular functioning. Mitochondrion has a matrix that is surrounded by two membranes called the inner membrane and the outer membrane. These two membranes are separated by an inter membrane space. The outer membrane has proteins embedded in them (most of which are porins- proteins that allow free transfer of molecules such as nutrients, ions, proteins etc.). While the outer membrane is smooth, the inner membrane is highly convoluted into structures called cristae to increase the surface area of the membrane. [1]
In The Immortal Life of Henrietta Lacks, multiple cell research studies involving Henrietta’s cells are described. Author Rebecca Skloot writes about Henrietta Lacks’ journey through her cervical cancer and how her cells changed the lives of millions long after her death. Skloot relates the history of cell research, including those studies which were successful and those that were not so successful. It is necessary for the author to include the achievements and disturbing practices of scientists throughout this history to inform readers and focus on the way Henrietta’s cells were used. Truth always matters to readers and Henrietta’s family deserves the truth.
Apfeldorf’s article “Uncovering a Tiny World” discusses Hooke’s book which is known for its microscopic illustrations of insects and microbes that Hooke had drawn as he viewed them under the microscope. His elaborate drawings of tiny objects and insects were the scientific evidence that supported his claims of the significant value of the microscope to science and the many ways it could be used. The book also contained a description of how to make a powerful microscope with a spherical lens, much like Leeuwenhoek’s glass pearls. Leeuwenhoek traveled to England that same year and is believed to have obtained a copy of Hooke’s book and
Q1.The cell cycle is the series of events which occur in a cell leading to its division and replication.
The cell cycle is the process by which cells progress and divide. In normal cells, the cell cycle is controlled by a complex series of signaling pathways by which a cell grows, replicates it’s DNA and divides, these are called proto-oncogenes. A proto-oncogene is a normal gene that could become an oncogene due to mutations. This process has mechanisms to ensure that errors are corrected, if they are not, the cells commit suicide (apoptosis). This process is tightly regulated by the genes within a cell’s nucleus. In cancer, as a result of genetic mutations, this process malfunctions, resulting in uncontrolled cell proliferation. Mutations in proto-oncogene or in a tumour suppressor gene allow a cancerous cell to grow and divide without the normal control imposed by the cell cycle. A change in the DNA sequence of the proto-oncogene gives rise to an oncogene, which
One can almost feel the searing penetration of Lewis Thomas’ analytical eye as it descends the narrow barrel of the microscope and explodes onto a scene of vigorous, animated, interactive little cells—cells inescapably engrossed in relaying messages to one another with every bump and bounce; with every brush of the elbow, lick of the stamp, and click of the mouse…
The mitochondria is an organelle which is generally an oval shape and is found inside the cytoplasm and is again apart of the eukaryotic cells. The main function of the mitochondria is to complete cellular respiration; in simple terms it acts like a digestive system to break down essential nutrients and to convert it into energy. This energy is usually found to in ATP which is a rich molecule taken from the energy stored in food. Furthermore, mitochondria stores calcium for signalling activities; such as heat, growth and death. They have two unique membranes and mitochondria isn’t found in human cells like the red blood cells yet liver and muscle cells are filled entirely with mitochondria.
In the late 1880s, genes, white blood cells, and aspirin were discovered. An Augustinian monk from Austria, Johann Gregor Mendel experimented in the crossplanting of pea plants. Eventually his research lead to the discovery of genes. In 1892, Elie Metchnikoff discovered phagocytosis. After observing the larvae of starfish, he found that mobile cells served as a defense for the organisms. This research on the cells lead him to believe that these cells swallow up and digest bacteria, therefore leading into the identification of white blood cells. Although it is unclear who deserves credit for the discovery of aspirin, Felix Hoffman and Heinrich Dreser are credited for the introduction. Both of them researched the drug while working for Bayer and they are credited for actually naming it "aspirin".
He was also the first to take a nucleus from a fully contrast tadpole intestinal
Mitochondria are small granular or filamentous bodies which are called the power house of the cell. They are associated with cellular respiration and are the sources of energy. In 1850, the German biologist Rudolph Kolliker first observed mitochondria as granular structures in striated muscle [Powar, C.B. 2010; Albert et al. 2010]. In 1898, the scientist Benda developed the crystal violet staining technique and called the structures mitochondria. The average length of the mitochondrion is 3-4 microns and the average diameter 0.5 to 1.0 micron. In muscles, most of the mitochondria are 2-3 microns long. Mitochondria have different shapes. The number of mitochondria is different in different types of cells of different organs. They are distributed evenly in the cytoplasm. In sperms they are present in tail, in muscles they lie between the myofibrils. Mitochondria may move freely in some cells. Where ever ATP required. Movement is less in animals than plants. In plants they change their shape and volume [Powar, C.B. 2010; Albert et al. 2010].
There are two main types of cells in the world. The simplest cells such as bacteria are known as Prokaryotic cells, and human cells are known as Eukaryotic cells. The main difference between each of these cells is that a eukaryotic cell has a nucleus and a membrane bound section in which the cell holds the main DNA which are building blocks of life.
The 1800’s was a time of development in science. New and what seemed like crazy ideas were surfacing. These ideas were more easily accepted than in past years. There were new theories such as the Cell Theory by Mathias Schleiden and Theodor Schwann in 1838 (Farah 626) and the Atomic Theory by John Dalton (Farah 628).A little over a decade after the Cell Theory was proposed, Louis Pasteur discovered bacteria in 1850 (Farah 627).
Because cells are the ‘basic unit of life’, the study of cells, cytology, can be considered one of the most important areas of biological research. Almost every day on the evening news, we are told about new discoveries in cell biology, such as cancer research, cloning, and embryology. (https://highered.mheducation.com/sites/0073031216/student_view0/exercise3/the_importance_of_cell_biology.html)
What is the cell cycle? It’s the way we reproduce. A series of events lead up from the beginning that which gives them life to the splitting of cells, The separate steps make up this very important process. Without the division of cells, we simply would not be here today.