Nursing Preparation Study Guide

Nursing Preparation Study Guide

Proteins Proteins are biological molecules that are made up of a chain or chains of amino acids. Proteins play many vital roles in living organisms. Protein is essential for the performance of many bodily functions, such as transporting nutrients andmolecules within the body, replicating DNA, responding to stimuli, and acting as a catalyst for metabolic reactions within the living organism, among other things. There are different types of proteins, each with a specific role. The difference in proteins is determined by their unique arrangement or sequence of amino acids. Genes A gene is a small part of the chromosome and is the molecular hereditary unity of an organism. It also used to describe a portion of RNA or DNA code that performs a particular function in the organism. Genes are essential to life because they specify the functions of all proteins and RNA chains. Genes contain the information to maintain and build the cells in the organism, and they hold genetic information that would be passed onto offspring. Genes house the information for biological traits and functions, some of which can clearly be seen and some that are hidden. For example, the information contained in specific genes determines factors, such as eye color, hair color, number of limbs, height, and so on. Some traits like blood type and the thousands of metabolic reactions and biochemical process that take place in the body to sustain life are defined unseen by the genes. A gene is a set of basic instructions embedded within a sequence of nucleic acids. The gene is a locatable region of the DNA genome sequence that corresponds with a unit of inheritance and is associated with a particular body function or set of functions. Chromosomes The chromosome is a piece of the DNA containing several genes. The chromosome is an organized part of the DNA. It is a single piece of coiled DNA. The chromosome contains several genes, DNA- bound proteins, nucleotide sequences and regulatory elements. The DNA-bound proteins help to hold the DNA together and regulate its functions. Since the chromosomes contain the genes, they contain almost all the genetic information of the organism. Chromosomes differ from one organism to another. The DNA molecule could be linear or circular. The chromosome can contain from 100,000 to over 3 million nucleotides in one long chain depending on the organism. Cells with defined nuclei (eukaryotic cells) usually have large, linear- shaped chromosomes. Cells without clearly defined nuclei (prokaryotic cells) typically have smaller sized circular chromosomes. Chromosomes are essential in the process of cell division. In mitosis cell division, the chromosomes have to be replicated and then divided between the two resulting daughter cells. This ensures that the resulting two daughter cells are genetically identical to the original mother cell.

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