Cells and Their Functions Study Guide
The Irreplaceable Role of Molecular Biology in the Health of Mankind
Molecular biology – This is a term that has recently gained in popularity. Most people do not really understand how this branch of biology works. This article will explain the definition of molecular biology and its irreplaceable role for the health of mankind.
What is Molecular Biology?
Molecular biology is a branch in biological science that combines two branches, namely Genetics and Biochemistry. It all began with the important discovery of the double helix structure of DNA by Watson and Crick in 1953. Both scientists were regarded as pioneers of molecular biology. Their findings inspired many other discoveries, one of which is very important, that genes determine proteins by regulating the order of nucleotides (in RNA) that ultimately compile the amino acid sequence in a protein. This was an important milestone in molecular biology! This milestone triggered a branch of genetic engineering that allows the isolation and multiplication of genes as a characteristic of this science.
The Central Role in Cell Life
All life forms in the universe originate from cells. Cells are what form the basis of all life forms and cell life is a representation of proteins (polypeptides) and DNA (genes). In traditional understanding, proteins act as enzymes that regulate the functionality of various organs in the body. Apart from being an enzyme, proteins are also responsible for the formation of cytoskeleton and matrix between cells, receptors, hormones, transcription factors, antibodies, etc. Some types of proteins play more roles; Regulation of cell proliferation and differentiation, organogenesis, histogenesis and apoptosis (associated with cell death). From this, we can understand the importance of proteins in human life and how genetic engineering processes depend heavily on the modification of the protein. All the attributes of all life forms are determined by the genes and they are governed by proteins.
Two Categories of Genes
Several types of genes have been discovered but scientists divide them into two main categories: Structural Genes and Regulatory Genes.
Structural genes are genes that encode amino acid sequences in proteins. We can take the enzyme as an example of the result of regulation by structural genes. Enzymes determine biochemical activity (related to catabolism and anabolic reactions) in every organism.
Regulatory genes serve as controllers or regulators for structural gene expression rates, protein production rates as well as cell responses, both intracellular and extracellular.
In other words, we can conclude that genes and proteins are inseparable and both determine the life of all organisms to the smallest point.
Progress in the Development of Molecular Biology towards Modern Medical Sciences
Modern medical sciences such as genetics, histology, embryology, physiology, parasitology, pathology, pharmacology, etc. are all strongly influenced by molecular biology through molecular therapy. We can find examples in the treatment of Severe Combined Immuno Deficiency (SCID) disease, thalassemia, hemophilia, cystic fibrosis and cancer. All use molecular therapy as a base (except for a few forms of cancer treatment).
Since the early 1960s, experts have attempted to manipulate cells. They began by isolating the constituent components such as DNA, as well as RNA as “close relatives of DNA” that serve as gene catalysts, gene expression controllers, and also respond to cellular signal stimulation. Unlike DNA, we can find RNA in the form of a single strand. Cell manipulation has a strong foundation of what is called a polymerase chain reaction (PCR). It is a manipulative reaction that makes it possible to alter acid-base DNA, amplify RNA, and also quantify the DNA molecule (and RNA). Molecular biology also provides theoretical basis for gel electrophoresis, which, in general, has the principle that DNA, RNA, and various other forms of proteins can be separated by using a particular electric field. For example, DNA and RNA can be separated by size using an SDS-PAGE gel based on the size of the protein and the required electrical charge. This is important in gene modification and we know that many diseases actually originate from functional deviations of genes.
DNA array is “a laboratory term” for a collection of spots attached to solid support such as a microscope slide, each of which holds one or more DNA fragments of oligonucleotides. This is classified as a technique that allows scientists to place micro spots (about 100 micrometers in size) on a slide. This modern technique functioned as a review of gene expression of an organism. In practical medicine, this technique is used to compare gene expression between two tissues; Healthy tissue and cancer tissue. We know that cancer is an event of cell mutation in high speed. The lay community identifies it as malignancy. By comparing gene expression (using array techniques) between the two networks, we can understand how the effect of genes works on both. Scientists have found that they can cure cancer by attacking the heart of the problem, gene mutation!
Treatment of the Disease is Caused by a Virus
We all know HIV, a dangerous virus that attacks the human immune system. This virus causes the condition of AIDS, one where the individual does not have resistance towards any disease. HIV has not been cured until now. This disease can only be controlled with the intake of certain drugs, commonly called as Antiretroviral Drugs, which have a major function as a preventer of viral replication. Viruses cannot be completely eliminated but they can be prevented from multiplying.
Three years ago, a group of US researchers claimed that they could fight HIV by editing the genome. They edited the patient’s genome so that they can develop resistance to fight the virus. The success was still within the scale of very early clinical research. The research paper was published in The New England Journal of Medicine.
Editing genome is a process of inserting, replacing, or removing certain genes from the genome. The genome editing process is assisted by nuclease compounds. It plays a vital role in cutting and connecting genes that are often called Molecular Shears. All these intricate processes stem from the important discovery of the double helical structure of DNA nearly 7 decades ago. All are covered in molecular biology and this is the reason why this branch of science has an irreplaceable role in the health of mankind.
Cell Study Guide Ch4 BI
Cell Study Guide
|What type of cells did Hooke view when he discovered cells?|
|What are the smallest units of life called?|
|Which increases faster, the surface area or the volume of a cell?|
|What limits how large a cell can grow?|
|What do you call organisms that do not have a nucleus?|
|Give an example of a prokaryote.|
|Name several eukaryotic cells.|
|What type of cells have membrane-bound organelles?|
|Prokaryotes have a cell membrane and a ___________ around the outside.|
|What are cell membranes?|
|Give 2-3 functions of the cell membrane.|
|The cell membrane is selectively permeable. What does this mean?|
|If a cell is very active and needs more energy, what type of organelle will it need more of?|
|What organelle makes a cell’s ATP?|
|Proteins are made by what organelle?|
|What organelle is the packaging & export center of the cell?|
|What double membrane surrounds the nucleus?|
|Name the 3 main parts to all eukaryotic cells.|
|What canals connect the nuclear membrane with the cell membrane for the movement of materials?|
|In what organelle are chromosomes found?|
|Name 2 structures found in plant cells but not in animal cells.|
|Where does photosynthesis occur in a cell?|
|In what organelles is the green pigment chlorophyll found?|
|What is the purpose of large vacuoles in plant cells?|
|List the levels of organization in order from simplest to most complex starting with the cell.|