Preview

Structure of Dna

Good Essays
Open Document
Open Document
891 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Structure of Dna
Every living organism is made of cells. Every cell has a nucleus, and every nucleus has chromosomes. Human beings have 46 chromosomes or 23 chromosome pairs and each chromosome contains hundreds of genes. These genes contain the recipes, for proteins that make most of the body. Structural proteins form things such as skin, hair, and muscle. These chromosomes are very long compact coils of DNA (Deoxyribonucleic Acid) that store all the information that the body inbeds such as how one looks and functions.
This paper will first describe the structure of DNA; second discuss how the structure of DNA allows it to serve as the basis for inheritance, third examine how meiosis allows DNA to be divided into gametes and finally, describe how this relates to Gregor Mendel’s patterns of inheritance.
The structure of DNA
DNA is a thread formed by two strands, related together to form a Double Helix. The Double Helix looks like a twisted ladder. The "sides" of this "ladder" are long units called nucleotides and are made of three parts; a nitrogenous base, a sugar, and a phosphate group. The sides of the ladder or the nucleotides from the two separate strands of the DNA are attached by an appendage made of one of four separate bases. These appendages represent the "rungs" of the DNA "ladder" and are attached to the complimentary strand or side of the DNA. The bases or “rungs” are made of either Adenine (A) and Thymine (T) or Cytosine (C) and Guanine (G). The attachment of the strands by the bases is specific as Adenine can only join with Thymine, and Cytosine can only join with Guanine. Since this base pairing is specific, if one knows the sequence of bases along one strand of the DNA one will also know the sequence along the complimentary strand.
DNA as a Basis for Inheritance
The unique pairing of the rungs of the DNA ladder is the basis for DNA acting as the molecule of inheritance. DNA duplicates in a process called DNA replication. This process involves the separation of

You May Also Find These Documents Helpful

  • Good Essays

    The bases in a strand of DNA relate to the base pairing rule due to the combination of GC and AT, make equal strand, that is held together by a hydrogen base.…

    • 877 Words
    • 4 Pages
    Good Essays
  • Good Essays

    Btec Level 3 Unit 25 D2

    • 1411 Words
    • 6 Pages

    Deoxyribose Nucleic Acid (DNA) is a polynucleotide molecule that encodes the genetic instructions used in the development and functioning of all known living organisms and many viruses. Most DNA molecules are double stranded helices, consisting of two polynucleotide strands made up of simpler molecules known as nucleotides. A nucleotide is made up of an organic nitrogenous base, a deoxyribose sugar and phosphate groups. It is order of these bases which make up the genetic code; a set of rules, by which information is encoded within genetic material.…

    • 1411 Words
    • 6 Pages
    Good Essays
  • Good Essays

    Dna Sci/230

    • 494 Words
    • 2 Pages

    DNA stands for Deoxyribonucleic acid and looks like a spiral. The spiral is also known as a double helix. The strands are made up of our genetic information, composed of genes and chromosomes. There are four bases divided among purines and pyrimidines. On the purines there are Adenine (A) and Guanine (G). On the pyrimidines there are Cytosine (C) and Thymine (T). The base pairs are Adenine and Thymine (A-T) and Cytosine and Guanine (C-G). DNA is found in the nucleus of every human cell. Humans have 46 chromosomes. When a cell reproduces, the chromosomes get copied and distributed to each offspring.…

    • 494 Words
    • 2 Pages
    Good Essays
  • Satisfactory Essays

    Sci 230 Dna

    • 490 Words
    • 2 Pages

    DNA is composed of two polynucleotide strands wound together into a structure known as a double helix. Each nucleotide consists of a sugar base .Nucleotides form together creating a sugar phosphate backbone to each strand. There are three forms of DNA that differ significantly. The most common, B form, is the structure most people have heard of. It consists of the right handed double helix, with a large major groove and a smaller but accessible minor groove. These grooves are spaces between the backbones which allow access to the bases for interactions with proteins. A form DNA is also a right handed helix, but as yet has not been found in organisms, and only exists in synthetic environments. It has a wider, flatter structure. Z form DNA is found in living organisms, but is a left handed helix, meaning it twists in the opposite direction.…

    • 490 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    Dna Worksheet

    • 472 Words
    • 2 Pages

    DNA made up of units called nucleotides, nucleotides are made up of three molecules components, a nitrogen base, a sugar, and a phosphate (Simon, Reece, Dickey, 2010). The nucleotides are joined together by bonds between the sugar of one nucleotide and the phosphate of the next producing a long chain of nucleotides resulting in a sugar-phosphate backbone (Simon, Reece, Dickey, 2010) the base containing nitrogen is the only part that is variable represented by, A Adenine, C cytosine, G guanine, and T Thymine. The sugars and phosphates form the backbone of the molecule and are on the outside. The bases point inwards horizontally. The antipoarallel strands run in opposite directions and are held together by hydrogen bonds between the base pairs, these two long strands twisted and wrap around each other to form a double helix. Hydrogen bonds between bases hold the strands together; each base pairs with a complementary partner: A with T, and G with C (Simon, Reece, Dickey, 2010).…

    • 472 Words
    • 2 Pages
    Good Essays
  • Satisfactory Essays

    Dna Work Sheet

    • 491 Words
    • 2 Pages

    Describe the structure of DNA.DNA is thread formed by two strands, related together to form a double helix. The double helix looks like a twisted ladder. The sides of this ladder are long unites called nucleotides and are made of three parts; a nitrogenous base, a sugar, and a phosphate group. The sides of the ladder or the nucleotides from the two separate strands of the DNA are attached by an appendage made of one of four separate bases. These appendages represent the rungs of the DNA ladder and are attached to the complimentary strand of the DNA. The bases or rungs are made of either Adenine (A) OR Thymine (T) or Cytosine (C) and Guanine (G). The attachment of the strands by the bases is specific Adenine can only join with Thymine, and Cytosine can only join with Guanine. Since this base pairing is specific, if one knows the sequence of bases a long one strand of the DNA one will also know the strand of the DNA one will also know the sequence along the complimentary strand.…

    • 491 Words
    • 2 Pages
    Satisfactory Essays
  • Powerful Essays

    DNA is made up of two strands. At one end of each strand there is a phosphate group attached to the carbon atom number 5 of the deoxyribose (this indicates the 5' terminal) and at the other end of each strand is a hydroxyl group attached to the carbon atom number 3 of the deoxyribose (this indicates the 3' terminal). The strands run in opposite directions and so we say that they are antiparallel. One strand runs in a 5'-3' direction and the other runs in a 3'-5' direction. Adjacent nucleotides are attached together via a bond between the phosphate group of one nucleotide and the carbon atom number 3 of the deoxyribose of the other nucleotide.…

    • 2219 Words
    • 9 Pages
    Powerful Essays
  • Satisfactory Essays

    Reversing Entries

    • 388 Words
    • 2 Pages

    A DNA molecule which is the abbreviation for deoxyribonucleic acid is made up of precise lengthy chains of polymers and monomers and they are called nucleotides. These two (2) chains specifically which are composed of DNA strain are then molded by the grouping of the nucleotides into the polynucleotides. The nucleotide is composed of a nitrogenous base, a phosphate and a group. In DNA there are four (4) nucleotides that can be found along the DNA chain. These four (4) nucleotides are (T) thyme, (A) adenine, (C) cytosine, and (G) guanine. These four (4) nucleotides are fused together by their covalent bonds. In other words the sugar and the phosphates which composes the sugar/phosphate support of the polynucleotide.…

    • 388 Words
    • 2 Pages
    Satisfactory Essays
  • Good Essays

    DNA Work Sheet

    • 506 Words
    • 3 Pages

    DNA is a nucleic acid, which consist of long chains (polymers) of chemical units (monomers) called nucleotide. A molecule of DNA contains two polynucleotides, each a chain of nucleotides. Each nucleotide consists of a nitrogenous base, a sugar, and a phosphate group. Each DNA strand serves as a mold, or template, to guide reproduction of the other strand. There are four different types of nucleotides found in DNA, differing only in the nitrogenous base. DNA is contained in blood, semen, skin cells, tissue, organs, muscle, brain cells, bone, teeth, hair, saliva, mucus, perspiration, fingernails, urine, feces, etc. The four nucleotides are given one letter abbreviations as shorthand for the four bases: A is for adenine, G is for guanine, C is for cytosine, and T is for thymine.…

    • 506 Words
    • 3 Pages
    Good Essays
  • Good Essays

    Steps and process of DNA

    • 1199 Words
    • 5 Pages

    Single Strand Binding Proteins attach to the halves and keep the DNA molecules separated (they are needed because the sides are attracted to each other and with out the Single Strand Binding Proteins they would move back together)…

    • 1199 Words
    • 5 Pages
    Good Essays
  • Better Essays

    Offspring differ somewhat from their parents and from one another. Instructions for development are passed from parents to offspring in thousands of discrete genes, each of which is now known to be a segment of a molecule of DNA. This essay will explore some of the reasons behind how and why these differences in appearance arise, from the base sequence of DNA through to the observed phenotype.…

    • 1961 Words
    • 8 Pages
    Better Essays
  • Good Essays

    DNA consists of two polynucleotide chains and these nucleotides consist of a deoxyribose sugar, a nitrogenous base and a phosphate group. The bases are Adenine, Cytosine, Guanine and Thymine. The sequence of these bases on DNA determines the structure of these proteins. A gene is a sequence of bases which codes for a single polypeptide. Chromosomes carry these genes and these genes come in specific forms called an allele which is how living organisms vary from each other. For example, humans are made up of an XY or XX chromosome. Females are XX and males are XY, however in some animals their sex is determined by the ZW sex-determination…

    • 768 Words
    • 2 Pages
    Good Essays
  • Good Essays

    Our body is made up of millions of cells, in every cell, except egg and sperm, we have 46 chromosomes, 23 pairs…

    • 3712 Words
    • 14 Pages
    Good Essays
  • Powerful Essays

    DNA is put in the in the class of compounds known as nucleic acids, which are polymers made out of the monomers. The monomers that make the polymers that construct DNA are called nucleotides. Two types of nucleic acids allow living organisms to copy their own complex components to their offspring through reproduction; deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Nucleic acids exist as polymers known as polynucleotides that all are made up of nucleotides. Nucleotides have only one phosphate group, and the part of a nucleotide without a phosphate group is known as a nucleoside.…

    • 1401 Words
    • 6 Pages
    Powerful Essays
  • Powerful Essays

    Human Genetic Engineering

    • 1539 Words
    • 7 Pages

    DNA looks something like a twisted staircase, and when in a condensed form, each DNA molecule is called a chromosome. Genes are formed in pairs are located in these chromosomes. During reproduction the gene pairs are split apart and randomly passed on to the offspring. During the replication of the gene pairs chance events such as mutations, can change their structure and prompt evolution.…

    • 1539 Words
    • 7 Pages
    Powerful Essays

Related Topics