Intro -The concept of the gene has been the focus of some hundred years of work to establish the basis of heredity, however there is no simple one line answer to the question what exactly is a gene. Genes have a variety of different functions a gene is a sequence of dna that carries information representing a protein. The sequence of dna can be identified as a continuous stretch stretch of nucleotides and chromosomes. Genes are made up of dna and act as instructions to make the molecule called proteins. Medal’s law of definition states that during production of two gametes through reproduction the two copies of each hereditary factor segregate so that offspring acquire one factor from each parent .mendal has three laws of gene types,inheritance,dominace and segregation,mendals second law summarizes the independent assortment of different genes, for example when a plant is dominant for two different characteristics is crossed with a parent that is recessive for both, for example if a human or a plant has a traits or characteristics that are recessive that means they are hidden but derived from their parents, then the recessive comes out as dominant when that human or plant reproduces offspring.
Structure of a gene- To understand a gene we must first realise the importance of chromosomes within cells. Chromosomes are responsible for are inheritance. Early experiments showed that a typical cell consists of a dense nucleus separated by a membrane from the less-dense surrounding cytoplasm within the nucleus, the granular region of chromatin. Chromosomes can be seen in most cells during the process of cell division, they are thread like structures of nucleic acids and protein found in the nucleus of most living cells carrying genetic i...
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...n as unstable alleles. Examples of this type of disease are Huntington's disease, and the myotonic form of muscular dystrophy.
Process of genetic expression-gene expression occurs throughout any organism`s life starting at the beginning, when an organism develops firstly as a zygote and later as an embryo. Genes turn on to regulate this process, cells begin exactly the same but this process changes their characteristics quickly, cells that have the ability to turn into any kind of tissue are totipotent. Cells get instructions from their dna to turn into certain kind of tissues such as skin and bone after the tissue type is decided certain genes in cells become active and others get permanently turned off. This is because gene expression is highly tissue-specific meaning certain genes are only active in certain tissues or in a particular stage of their development.
No one knew how heredity (passing traits) worked until Gregor Mendel, an Austrian monk, crossbred pea plants in his monastery kitchen garden in 1865. In 1869, gene-hunters found rod-like shape in the nucleus of cells that turned red when dye was added. They named this “Chromosome”, from a Greek word, chroma for color. They also went deeper into the cell and discovered a wispy microscopic thread within the chromosomes, which they named DNA. There were several scientists who did not know about Mendel’s breakthrough at the time, but then in 1900, they rediscovered his experiment and old journal copies.
[7] Klug, W., Cummings, M., Spencer, C., Palladino M. (2012) Concepts of Genetics: Tenth Edition. Pearson's Education, Inc.
There are 4 main mechanisms of modification and regulation of gene expression; DNA methylation, Chromatin Remodeling (architecture), Histone Modification and RNAi (interference/interactions)
All cells contain a complex structure known as deoxyribonucleic acid (DNA). DNA is a chemical that determines how we are. The multiple combinations of its components are what makes a difference in each person. Long molecules of DNA are organized into chromosomes, which are grouped into 23 pairs. Then the chromosomes are broken down into short segments of DNA known as genes.
This encyclopedia was extremely helpful. In not knowing all of the exact terms and basic knowledge of genetic engineering, it helped inform any reader of all this and more. The pages that had information on genetics and genetic engineering, had detailed definitions and descriptions for all the terms and ideas. Instead of focusing more towards the future of genetic engineering, it gave numerous facts about the technology and accomplishments of today. In addition to basic knowledge information, history, diagrams, and background information was provided. Including genetic testing, genes and their formation, and genetic background. The encyclopedia gave easy, organized, and accessible information to use.
A debate between psychologist, scientists and philosopher thinkers on the spectrum of ‘nature vs. nurture’ arose concerning human development. In the nature versus nurture debate, the term "nature" refers to the genes we inherit while the term "nurture" refers to our outside environment (Nature vs. Nurture: Twin and Adoption Studies). This debate of ‘nature vs. nurture’ has existed for centuries and up to now it is still a topic of major discussion although at present time. Human development is the scientific study of age-related changes in behavior, thinking, emotions and personality (Boyd & Bee, 2005). In order to understand cognitive, emotional, physical, social and educational growth that everyone experiences from childhood until adulthood, we must first understand the influence and importance of child development. Different psychologists have different theories and concepts of child development. Grand theories often use a stage-by-stage approach while attempting to describe the areas of development. Mini-theories focus only on a fairly limited aspect of development, such as cognitive or social growth. (Cherry, Child Development Theories, 2011)
Many people have wondered what it is exactly that makes us...human. What is it that separates us from one another that makes us unique? DNA and Genes is what makes every person up. Everyone is different because of it. Humans are different from each other by their skin color, their facial features, and it’s all due to Deoxyribonucleic Acid. DNA or Deoxyribonucleic Acid is a molecule that contains the genetic instructions that are used in the functioning, the development, and the reproduction that is a necessity to humans and other living organisms.
Huntington’s disease is a progressive neurological disorder that is caused by an autosomal dominant mutation in the HTT gene. There will be no change in the allele frequencies because this treatment only has an effect on the phenotype, not the genotype; it does not
Eukaryotic cells have their chromosomes contained in a nucleus. Unicellular orgasisms such as amoebas and yeast, or multi-cellular organisms such as plants and animals consist of eukaryotic cells. Human being consist of approximately 1 billion cells per gram tissue. DNA located in 23 pairs of chromosomes is contained in each cell nucleus. Schleiden in 1838 and Schwann in 1839 made very important discoveries that we consist of cells, and Remark discovered that cells prolifarate through division in 1850. Three decades ago, the molecular mechanisms that regulate the cell cycle and thus cell division was able to be identified. It has been known that these vital mechanisms are conserved through evolution and function in the same way in eukaryotic organisms.
A chromosome is made up of two identical structures called chromatids. The process of nuclear division is called interphase; each DNA molecule in a nucleus makes an identical copy of itself. Each copy is contained in the chromatid and a characteristic narrow region called the centromere holds the two chromatids together. The centromere can be found anywhere along a chromosome but the position is the characteristic for a particular chromosome. Each Chromatid contains one DNA molecule. DNA is the molecule of inheritance and is made up of a series of genes. The fact that the two DNA molecules in the sister chromatids, and hence their genes, are identical is the key to precise nuclear division.
Genetics defined as the study of heredity of genetic material from parents to offspring. In 1865, Gregor Mendel (the father of genetics) conducted experiments on pea plants led to the birth of genetics. He recorded his observation accurately by studying one trait at a time. Mendel used different variable factor during his experiments. For example, he used the height of the plant, the shape of the seed, and the color of the seed. He discovered three laws which called the Mendel principles. These laws were: law of dominance, law of segregation, and law of independent assortment (Michael J. Simmons, 2015). The law of dominance defined as one allele during heterozygote condition is dominate over the other allele. Meanwhile, the law of segregation
All individuals, except identical twins, have unique DNA. DNA fingerprinting is an unambiguous identification method that takes advantage of the difference in the DNA sequence. This process of DNA fingerprinting starts with the isolation of the DNA from the identified sample, such as blood, saliva, semen or other body tissues. In instances where the available sample is small for the process of fingerprinting, then the sample is augmented through a process called polymerase chain reaction (PCR). PCR is the process of DNA replication that does not use living cells and, therefore, the process is appropriate in fingerprinting old samples. The focus of this process is on the short tandem repeats (STR) that have short units of DNA that are repeated several times in a row. After the DNA is isolated and amplified it is treated with restriction enzymes. This process cuts the DNA strands at definite sequences called restriction fragment length polymorphisms (RFLPs). Since everybody’s DNA is different the resulting RFLPs will be of different sizes. These fragments are observed in gel electrophoresis; a process that separates DNA based on the size of fragments. RFLP analysis is based on the fact that since everyone’s genetic sequence or the variable number of tandem repeats is different this result in the different sizes of RFLPs. Gel electrophoresis involve the separation of the fragments of DNA as they migrate through an agarose gel when an electric current is applied to the gel. The DNA that has separated is then drawn out of the gel with a nylon membrane which is treated to break the hydrogen bonds holding the DNA strands together. The separated strands of the DNA is then cross-linked to the nylon membrane a...
A specialized cellular molecule copies a given sequence of DNA whose end product will contribute to its function. DNA is a long molecule that usually can be found in a condensed state. Specialized types of proteins called histones wrap the DNA, forming nucleosomes, and thus occupying a smaller volume in the nucleus. There are 2 types of nucleosomes, their importance being in that they tell what will be expressed or not. Euchromat...
Genes from parents are passed down to their children and this sets up their lifelong development. When a male cell meets with female reproductive cell, they start a process for a new life in a woman’s womb. The sperm has a different copy of the gene and an egg the same and so when they meet, two copies of genes are present and through them a new life begins and it will comprise both genes. From the eyes to the color of the hair, genetics plays a role in a person’s biological make up and development. Genes can predetermine many different characteristics in human development.