DNA Structure Basics

The name indicates that DNA contains Deoxyribose (a 5-carbon sugar) and is a Nucleic Acid (molecule made up of nucleotides)

The three components are a sugar molecule, a nitrogen base, and a phosphate group, which are joined together to form the nucleotides that make up the DNA molecule

The nitrogen bases form the 'letters' of the genetic code, and they pair with each other to form the rungs of the DNA molecule

<p>The double helix structure of DNA allows for the pairing of nitrogen bases, which enables the storage and transmission of genetic information</p> Signup and view all the answers

<p>The sugar-phosphate backbone provides a structural framework for the nitrogen bases to pair with each other, forming the rungs of the DNA molecule</p> Signup and view all the answers

<p>The double helix shape allows for the compact storage of genetic information and provides a mechanism for the replication of DNA</p> Signup and view all the answers

<p>Rosalind Franklin's 1952 X-ray diffraction image of DNA showed that DNA was probably a helix, and it was used by James Watson and Francis Crick without her knowledge or permission to identify the double helix structure of DNA.</p> Signup and view all the answers

<p>The base pairing rules in DNA are based on the number of hydrogen bonds that can form between each base, with Adenine (A) and Thymine (T) making 2 hydrogen bonds, and Guanine (G) and Cytosine (C) making 3 hydrogen bonds. This means that A can only bond with T, and G can only bond with C.</p> Signup and view all the answers

<p>A gene is a section of a DNA molecule that contains instructions to produce a particular protein or carry out a specific function. It is a unit of heredity that codes for a particular trait.</p> Signup and view all the answers

<p>The two strands of nucleotides in DNA form a double helix structure through hydrogen bonds between the base pairs, with Adenine (A) pairing with Thymine (T) and Guanine (G) pairing with Cytosine (C).</p> Signup and view all the answers

<p>The genome is the total set of genes within an organism, and it is organised into chromosomes, which are larger structures that contain many genes along their length.</p> Signup and view all the answers

<p>The complementary DNA strand would be TAGTGCGCTAATTCCTGGACCTTCTT.</p> Signup and view all the answers

<p>A chromosome is a long, thin, thread-like structure of DNA wrapped around proteins. The proteins help to organize and compact the DNA, allowing it to fit within the nucleus of a cell.</p> Signup and view all the answers

<p>The term 'locus' refers to the physical position of a gene on a chromosome. The plural form of the term is 'loci'.</p> Signup and view all the answers

<p>Prokaryotic cells lack a nucleus, and their DNA is found in a single circular chromosome. Eukaryotic cells have a nucleus, and their DNA is organized into linear chromosomes. This difference greatly impacts the organization and regulation of genes.</p> Signup and view all the answers

<p>The double helix model of DNA describes the twisted, ladder-like structure of DNA. This structure is due to the pairing of nitrogen bases, with adenine bonding with thymine and guanine bonding with cytosine.</p> Signup and view all the answers

<p>Hydrogen bonds are weak bonds that hold the two strands of DNA together. They are formed between the nitrogen bases, and are important for the stability of the double helix structure. Covalent bonds, on the other hand, are strong bonds that hold the sugar and phosphate molecules together to form the backbone of DNA.</p> Signup and view all the answers

<p>The sequence of nitrogen bases in DNA determines the code for amino acids, which are used to build proteins. These proteins, in turn, determine the traits of an organism. The sequence of nitrogen bases ultimately determines the physical characteristics of an organism.</p> Signup and view all the answers