3. DNA

6. Structure

7. Replication

8. Gene expression

9. Mutations

10. Video

11. Bibliography

14. Altmann identified the

15. acids and gave them

16. the name nucleic

17. acids.

22. Hershey and Martha

23. Chase conducted a

24. series of experiments

25. to determine whether

26. DNA or protein was

27. the hereditary

28. material.

30. STRUCTURE Each DNA molecule consists of two chains formed by a large number of chemical compounds called nucleotides .

31. Each nucleotide consists of three units: a sugar molecule (desoxyribose), a phosphate group and one of four possible nitrogen compounds called bases: adenine (A), guanine (G), thymine (T) and cytosine (C).

32. Containing adenine nucleotides are coupled always with thymine, and cytosine with guanine. The complementary bases are joined together by weak chemical bonds called hydrogen bonds .

33. Deoxyribonucleic acid is a polymer of two antiparallel strands (orientation 5 '3'y3'5').

34. REPLICATION The DNA replication process allows the DNA to double, ie, synthesize an identical copy.

35. This duplication of genetic material occurs according to a semiconservative mechanism(the chain of the DNA is previous ).

37. DNA polymerases give each daughter cell a DNA copy of the original in the process of mitosis. They carry out the synthesis of new DNA strand matching the deoxyribonucleotide triphosphate.

38. Primer is a iniciator of the creation of the chain delayed (so called because its direction is 3-5).

39. DNA polymerase III is the principal responsible enzyme for DNA elongation (polymerase activity 5 '-> 3'). It also performs tasks of correction (exonuclease activity 3 '-> 5').

40. DNA polymerase | (adds 20 to 100 nucleotides per binding event) is responsible for the elimination of primers and the "filling" the space left by DNA.

41. DNA ligase is a enzyme with forms links between 5 'end of a chain end and 3 'of another string.

42. Gene expression DNA -> RNA -> protein: gene expression. To express the genetic information contained in DNA, first the nucleotide sequence of a gene is transcribed into RNA. The transcript is catalyzed by the enzyme RNA polymerase.

43. The sequences of the nucleotids of DNA's molecules indicate to RNA polymerasa where to start and where to finish the transcription.

46. Most genes are divided into small coding regions (exons) interspersed with noncoding regions (introns) .

47. At the core, the introns are removed from the primary RNA transcript through a process of maturation of RNA. By a reaction catalyzed by small ribonucleoprotein complexes known as snRNPs, the introns are excised from the primary transcript and exons are joined together directly. Then the mRNA moves to cytoplasm.

48. The nucleotide sequence of the mRNA is read in groups of three nucleotides ( codons ), so that each codon corresponds to an aminoacid.

49. The possible combinations of four different nucleotides in the RNA produced 64 different codons in the genetic code. Most amino acids are specified by more than one codon.

53. TYPES : gene, chromosome and numerical.

54. Gene: affects the chemical structure of genes. MUTATIONS

56. Types:

57. a) Deletion b) Duplication

59. Numerical: The disorder affects the number of chromosomes. There are two types: euploidias: affect the number of chromosomes: aneuploidy : missing or overrun chromosomes.

60. Causes of mutations Mutagenic agents can be: physical (X-ray,radiation) chemicals (pesticidios, dyes, smoke snuff) biological (human papillomavirus)

61. Autosomal disorders Dominant alleles: Polydactyly Syndactyly Brachydactyly

62. Recessive alleles: Albinism Anemia

63. Autosomal disorders The most frequent are trisomies. Down syndrome (trisomy 21): Features: Mental retardation Mongoloid facial features Various disorders (eye, heart ...)

65. Patau syndrome(trisomy 13): Features: Mental retardation Cardiac malformations Absence of palate

66. Sex chromosomes Women are affected: Triple X syndrome (3 X) Features: Mental retardation Neuropsychiatric disorders

68. Men are affected: Double Y syndrome(Y and 2X) Features: Skeletal malformations Mild mental retardation

71. Features:

72. Produces heart failure and microcephaly, profound mental retardation.

73. VIDEO http://www.youtube.com/watch?v=qy8dk5iS1f0 http://www.youtube.com/watch?v=xS-jRRJWU14&feature=related

75. Information sent by the teacher http://es.wikipedia.org/wiki/ADN_recombinante http://www.monografias.com/trabajos12/desox/desox.shtml http://biomodel.uah.es/model4/dna/index.htm http://www.galileog.com/ciencia/biologia/adn/adn1.htm#descubrimiento http://cerezo.pntic.mec.es/~jlacaden/webmec16/defi_mental12.html Biology and Geology(oxford education) 4º E.S.O.

76. Images http://www.google.es/images?um=1&hl=es&rls=com.microsoft%3Aes%3AIE- http://www.google.es/images?um=1&hl=es&rls=com.microsoft%3Aes%3AIE-&tbs=isch%3A1&sa=1&q=Johann+Friedrich+DNA&aq=f&aqi=g1&aql=&oq=&gs_rfai http://www.familyoldphotos.com/pa/images2/mar/richardaltman1.jpg http://bifi.es/jsancho/estructuramacromoleculas/11nucleotidos/adenina.JPG http://bifi.es/jsancho/estructuramacromoleculas/11nucleotidos/timina2.JPG http://fmc.unizar.es/people/fff/Jsancho2/citosina.JPG http://www.daviddarling.info/images/guanine.jpg http://timetoeatthedogs.files.wordpress.com/2008/05/watson-crick.jpg http://www.biology-blog.com/images/blogs/10-2006/seal-dna-breaks-0921.jpg http://html.rincondelvago.com/000567043.png http://aristotelizar.com/web/wp-content/2009/01/72.jpg http://www.intramed.net/UserFiles/imagenes/patau1.JPG http://www2.uah.es/genetica_juangonzalez/GeneticaHumana/Temario/Tema5/Imagenes-5/sindromeEdwards.gif http://www.childrenshospital.org/az/Site1036/Images/syndactyly.jpg http://oneparticularwave.files.wordpress.com/2006/04/496px-Polydactyly_01_Lhand_AP.jpg http://www.uic.edu/classes/phys/phys461/phys450/ANJUM04/RNA_sstrand.jpg Information sent by the teacher http://media.photobucket.com/image/albinismo/Vogelfray/albinismo.jpg http://ntic.uson.mx/wikisalud/images/5/5f/Sickle-cell-anemia.jpgç http://www.quimicaviva.qb.fcen.uba.ar/contratapa/aprendiendo/capitulo18_files/image007.jpg http://www.g2conline.info/content/c16/16406/16406_hershey_chase.jpg