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Genetic Mapping in Drosophila melanogaster
Genetic Mapping in Drosophila melanogaster

... T. H. Morgan, a geneticist who worked in the early part of the twentieth century, pioneered the use of the fruit fly, Drosophila melanogaster, as a model organism in genetic studies. Drosophila has a diploid chromosome number of eight, or four pairs of homologous chromosomes numbered 1 - 4. Chromoso ...
English
English

... come from the father and half from the mother.  This passing of traits from parents to offspring is called heredity. Not all differences in animals are caused by genetics. Some are caused by the conditions under which the animal is raised. ...
principles of inheritance and variation
principles of inheritance and variation

... trait. The affected individual lacks an enzyme that converts the amino acid phenylalanine into tyrosine.  As a result of this phenylalanine is accumulated and converted into phenylpyruvic acidand other derivatives.  Accumulation of these in brain results in mental retardation. These are also excre ...
Airgas template
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... only one member of the gene pair is affected. A teratogenic agent is an environmental agent that produces abnormalities only during the first 4 weeks of embryonic or fetal development. Down syndrome, Turner syndrome, and Klinefelter syndrome are all examples of chromosomal disorders that occur from ...
Pedigrees/Sex-linked traits - Liberty Union High School District
Pedigrees/Sex-linked traits - Liberty Union High School District

Heredity and Genetics - Olympic High School Home Page
Heredity and Genetics - Olympic High School Home Page

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... • Another related challenge is understanding the genome’s threedimensional shape. Far from being arranged in a line, chromosomes are folded in fantastically complicated fractal patterns, and these topographies appear to shape network interaction. • “Every gene is surrounded by an ocean of regulator ...
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ppt - Science with Ms. Wood!

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Chapter 9 - Sacred Heart Academy
Chapter 9 - Sacred Heart Academy

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Article Full Text  - Knowledge Bank
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... SC.6.L.14.2: Investigate and explain the components of the scientific theory of cells (cell theory): all organisms are composed of cells (single-celled or multi-cellular), all cells come from pre-existing cells, and cells are the basic unit of life. SC.7.L.16.3: Compare and contrast the general proc ...
Challenge Questions
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... Determine the outcome of inheritance crosses involving linked and sex‐linked genes.   Describe the structure of a chromosome.   Describe the process of mitosis and meiosis.  Define the term mutation and identify ways in which mutations may affect an organism   Identify the causes of mutations   Diff ...
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... 2. Vesicles are formed during a. protein synthesis. b. endocytosis. c. cellular respiration. ...
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...  Process that divides one diploid cell into four haploid cells.  Broken into Meiosis I and Meiosis II. ...
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Complementary DNA Sequencing: Expressed Sequence Tags and
Complementary DNA Sequencing: Expressed Sequence Tags and

... • Using ESTs will provide a better way of anayzing chromosomes and discovering more human genes. • EST method will result in partial sequencing of most human brain cDNAs in a couple years → further identification of genes involved in neurological diseases. ...
How was DNA shown to be the genetic material?
How was DNA shown to be the genetic material?

... postulated genetic factors (genes). Why was Mendel's work finally appreciated? A general understanding of Mendel's work had to wait until chromosomes were discovered. These structures provided a physical basis that could account for the behavior of the particles of inheritance. In 1903 Sutton publis ...
Biotechnology II PPT
Biotechnology II PPT

... 3. The radioactive probe will join with the complimentary bases on the gene of ...
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Chromosome



A chromosome (chromo- + -some) is a packaged and organized structure containing most of the DNA of a living organism. It is not usually found on its own, but rather is complexed with many structural proteins called histones as well as associated transcription (copying of genetic sequences) factors and several other macromolecules. Two ""sister"" chromatids (half a chromosome) join together at a protein junction called a centromere. Chromosomes are normally visible under a light microscope only when the cell is undergoing mitosis. Even then, the full chromosome containing both joined sister chromatids becomes visible only during a sequence of mitosis known as metaphase (when chromosomes align together, attached to the mitotic spindle and prepare to divide). This DNA and its associated proteins and macromolecules is collectively known as chromatin, which is further packaged along with its associated molecules into a discrete structure called a nucleosome. Chromatin is present in most cells, with a few exceptions - erythrocytes for example. Occurring only in the nucleus of eukaryotic cells, chromatin composes the vast majority of all DNA, except for a small amount inherited maternally which is found in mitochondria. In prokaryotic cells, chromatin occurs free-floating in cytoplasm, as these cells lack organelles and a defined nucleus. The main information-carrying macromolecule is a single piece of coiled double-stranded DNA, containing many genes, regulatory elements and other noncoding DNA. The DNA-bound macromolecules are proteins, which serve to package the DNA and control its functions. Chromosomes vary widely between different organisms. Some species such as certain bacteria also contain plasmids or other extrachromosomal DNA. These are circular structures in the cytoplasm which contain cellular DNA and play a role in horizontal gene transfer.Compaction of the duplicated chromosomes during cell division (mitosis or meiosis) results either in a four-arm structure (pictured to the right) if the centromere is located in the middle of the chromosome or a two-arm structure if the centromere is located near one of the ends. Chromosomal recombination during meiosis and subsequent sexual reproduction plays a vital role in genetic diversity. If these structures are manipulated incorrectly, through processes known as chromosomal instability and translocation, the cell may undergo mitotic catastrophe and die, or it may unexpectedly evade apoptosis leading to the progression of cancer.In prokaryotes (see nucleoids) and viruses, the DNA is often densely packed and organized. In the case of archaea by homologs to eukaryotic histones, in the case of bacteria by histone-like proteins. Small circular genomes called plasmids are often found in bacteria and also in mitochondria and chloroplasts, reflecting their bacterial origins.
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