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DNA & RNA: Structure and Functions 11.1 – 11.3. Page 280 - 295. Objective 8.0:12 Questions Identify the structure and function of DNA, RNA, and protein. Explaining relationships among DNA, genes, and chromosomes
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DNA & RNA: Structure and Functions 11.1 – 11.3 Page 280 - 295 Hickox: Baker Biology
Objective 8.0:12 Questions • Identify the structure and function of DNA, RNA, and protein. • Explaining relationships among DNA, genes, and chromosomes • Listing significant contributions of biotechnology to society, including agricultural and medical practice Examples: DNA fingerprinting, insulin, growth hormone • Relating normal patterns of genetic inheritance to genetic variation Example: crossing over • Relating ways chance, mutagens, and genetic engineering increase diversity/insertion, deletion, translocation, inversion, recombinant DNA • Relating genetic disorders and disease to patterns of genetic inheritance- ex – hemophilia, sickle cell anemia, down’s syndrome, Tay-Sachs disease, cystic fibrosis, color blindness, phenylketonuria (PKU) • Rosalind Franklin died of cancer at an early age. Her cancer was probably caused by the X rays she worked with to create photographs of DNA. • The differences observed between two individuals are 2 million to 10 million nucleotide base pairs out of 3 billion---only 1 percent of the total DNA. • Childhood cancers are probably caused by exposure in the womb to environmental and industrial pollutants that have been inhaled by the mother. • In all organisms, the instructions for specifying the characteristics of the organism are carried in DNA, a nucleic acid formed from subunits of four kinds (A, G, C, and T). The chemical and structural properties of DNA explain how the genetic information that underlies heredity is both encoded in genes (as a string of molecular "letters") and replicated (by a tinplating mechanism). Each DNA molecule in a cell forms a single chromosome. Each chromosome is made of many genes. • Double helix, Nucleotide, DNA, Adenine, Guanine, Cytosine, Thymine, Replication Hickox: Baker Biology
Traits are determined by proteins that are built according to instructions specified in an organism’s DNA. The instructions are transferred from a gene to an RNA molecule in a process called transcription. Cells then use two different types of RNA to read the instructions on the RNA molecule and put together the amino acids that make up the protein in a process called translation. In addition to other functions, proteins can function as enzymes • RNA, Insertion, Transcription, Deletion. Translation, Translocation, Genetic code , Inversion, Transfer RNA, Recombinant DNA, Ribosomal RNA , Amino Acid,Uracil, Enzymes • The fact that the human body is formed from cells that contain two copies of each chromosome--and therefore two copies of each gene--explains many features of human heredity, such as how variations that are hidden in one generation can be expressed in the next. Crossing-over occurs when portions of a chromatid on one homologous chromosome are broken and exchanged with the corresponding portions on one of the chromatids of the other homologous chromosome. This adds more recombination to the independent assortment of chromosomes that occurs later in meiosis. The number of genetic combinations that can occur among gametes is practically unlimited. • Crossing over, Chromosome,Gene, Chromatid • Biotechnology has made significant contributions to society, especially in the areas of agriculture and medicine. The process of manipulating genes for practical purposes is called genetic engineering. Most of the cells in a human contain two copies of each of 22 different chromosomes. In addition, there is a pair of chromosomes that determines sex: a female contains two X chromosomes and a male contains one X and one Y chromosome. Transmission of genetic information to offspring occurs through egg and sperm cells that contain only one representative from each chromosome pair. An egg and a sperm unite to form a new individual. The fact that the human body is formed from cells that contain two copies of each chromosome--and therefore two copies of each gene--explains many features of human heredity, such as how variations that are hidden in one generation can be expressed in the next. • DNA fingerprinting, cystic fibrosis, Insulin, color blindness, Growth Hormone, phenylketonuria, Hemophilia, Tay-Sachs disease ,sickle cell anemia, Down’s syndrome Hickox: Baker Biology
What is DNA? proteins 1. Your skin, muscles, and bones contain _____________. 2. All actions depend on proteins called _____________, that speed up reactions. 3. Within _______is the information for life, containing the instructions to make all the different proteins an organism needs. enzymes DNA Hickox: Baker Biology
How can DNA hold all that information? structure 4. The amazing amounts of information can exist because of its ___________. 5. DNA is very long made up of repeating sub units called ____________. 6. A nucleotides is made up of: 7. A sugar 8. A phosphate group 9. A nitrogenous base 10. Adenine (_____) 11. Guanine (_____) 12. Cytosine (_____) 13.Thymine (_____) nucleotides A G c T Hickox: Baker Biology
What does the DNA molecule look like? double helix 13. Watson and Crick described the structure as two strands of nucleotides, a __________________held together by nitrogenous bases 14. sugar group 15.phosphate group 16. nitrogenous bases
How can DNA do so much with so little? four (4) 17. Made up of _________ nucleotides. 18. The key is the sequence or order of the four nucleotides. 19. It is the sequence of nucleotides that forms the genetic information for every organism. • Adenine (A) • Guanine (G) • Cytosine (C) • Thymine (T) Purines(two rings) Pyrimidines (one ring) Hickox: Baker Biology Chapter 11
Replication of DNA 20. DNA is made of two strands of nucleotides joined together like a zipper at the ____________ ______ 21. A) bonds with (T) and (C) bonds with (G) always! nitrogenous bases 22. Nucleotide 23. Hydrogen bonds 24. Deoxyribose Sugar-phosphate backbone Key Adenine (A) Thymine (T) Cytosine (C) Guanine (G) Hickox: Baker Biology
Watson & Crick Model Ch 11 Chapter 11 Hickox: Baker Biology
How does DNAREPLICATE? Ch 11 unzips separates • 25. The DNA molecule __________and ____________. • 26. As the DNA unzips, nucleotides are ________________in the cell and begin attaching to the unzipped chain. • 27.Each new strand formed is a ___________of one of the original strand. When all the chromosomes are replicated the cell can divide, passing on the genetic information to the new cell. Free floating complement Hickox: Baker Biology Chapter 11
DNA REPLICATION Ch 11 • 28. What is the complementary strand of bases: • TACGTT? ___________________ • 29. __________ are important in this process of “unzipping” and “zipping” these strands • 30. Because enzymes are involved with this process, DNA replication, the enzyme designed for this process is called: • ________________________ ATGCAA ENZYMES DNA POLYMERASE Hickox: Baker Biology Chapter 11
FROM DNA TO PROTEIN Ch 11.2 proteins 31. DNA contains information used to make ___________ 32. All this information is based on the sequence of nucleotides in the DNA molecule. RNA (three types) DNA gives the instructions to make _____________. ___________ RNA (mRNA) brings the information from the DNA to the cytoplasm. The _____________ RNA (rRNA) binds to the mRNA and use the instructions to assemble the amino acids in the right order. ____________ RNA (tRNA) delivers amino acids to the ribosomes to be made into proteins. proteins messenger ribosomal transfer Hickox: Baker Biology Chapter 11.2
Ch 11. 2RNA and Protein Synthesis RNA Structure 35. Genes are coded DNA instructions that control the production of proteins within the cell. 36. An RNA molecule is a polymer composed of subunits known as___________. Steps 37. Copy nucleotide sequence from DNA into RNA 38. RNA then carry out the process of making ______________ nucleotides PROTEINS Hickox: Baker Biology Chapter 11
Ch 11.2 RNA Structure 39. long chain nucleotides 40. single strand 41. contains __________ in place of thymine (T) 42. a “disposable copy” of a segment of DNA 43. could be even a “working copy” of a single gene URACIL (U) Hickox: Baker Biology Chapter 11.2
Ch 11.2 TYPES OF RNA AMINO ACIDS 44. the assembly of ___________ into proteins is controlled by RNA 45. __________________carries copies of instructions for assembly of amino acids into proteins 46. Ribosomes are made of rRNA and protein. 47. ___________________ are responsible for carrying or transferring Amino Acid molecules to ribosome. (m RNA) Messenger RNA (t RNA) Transfer RNA Hickox: Baker Biology Chapter 11.2
Ch 11-2 TRANSCRIPTION: Messenger RNA is formed • RNA molecules are produced by copying part of the DNAsequence called _____________________ • Required enzyme: ______________________ • Uses one strand of DNA as a template to assemble a strand of RNA TRANSCRIPTION RNA polymerase Hickox: Baker Biology Hickox: Baker Biology 17 Chapter 11.`2
TRANSCRIPTION: Messenger RNA is formed Adenine (DNA and RNA) Cystosine (DNA and RNA) Guanine(DNA and RNA) Thymine (DNA only) Uracil (RNA only) 51. Nucleus 48. RNApolymerase 49. DNA 50. mRNA Hickox: Baker Biology
What does RNA look like? single 52. RNA is a ________ strand 53. Looks like one half of a zipper 54. RNA also has______ nitrogenous bases but instead of thymine (T), RNA has ________ (U) that binds with adenine (A). 55. ______________RNA has to be made. 56. RNA is made from part of a ______ 57. Free RNA nucleotides form a strand by bonding together 58. RNA strand leaves the __________and enters the ______________. four uracil Transcription m(messenger) DNA nucleus cytoplasm Hickox: Baker Biology
Ch 11.2 THE GENETIC CODE • 59. Remember? The nucleotide sequence transcribed from DNA to a strand of mRNA is a genetic message that has all the information needed to build a protein. Proteins are made up of _________ _______. • 60. There are _____ different amino acids • 61. The “language” of mRNA instructions is called the _______________. • 62.The code is written in 3 letters of these: ________ amino acids 20 GENETIC CODE A, U, C and G Hickox: Baker Biology Page 292 Chapter 11.2
Ch 11.2 The Genetic Code • 62. The Genetic code is read 3 letters at a time • 63. Each word therefore is 3 bases long • 64. Each 3 letter word in mRNA is known as a __________. • 65. A codon consists of _____ consecutive nucleotides that specify a single amino acid • 66. With 4 different bases, there are 64 possible codons of the genetic code • 67. Special codons: • Start protein synthesis: AUG (methionine) • Stop (end of polypeptide): UAG, UAA, & ________ codon 3 UGA Hickox: Baker Biology Chapter 11.2
Genetic code (20 amino acids) Hickox: Baker Biology
Cracking the Code What are the STOP CODONS? What is the START CODON? Hickox: Baker Biology
Translation ! From mRNA to protein Ch 11.2 68. The _______ moves to the cytoplasm. 69. The _______ attaches itself to the start codon (AUG) on the mRNA. 70. _______ carrying the amino acid approaches the ribosome. For every codon on the mRNA there is an __________ on the tRNA. 71. The ribosome attaches the anticodon to the codon, the amino acids bond, and the ribosome slides over. 72. this translation continues until a ______ codon stops translation. mRNA rRNA tRNA anticodon stop Hickox: Baker Biology Chapter 11.2
Section 11.2 A: Transcription from the DNA in the nucleus into mRNA and is released in the cytoplasm Nucleus Messenger RNA Messenger RNA is transcribed in the nucleus. mRNA 74.Lysine 80.Phenylalanine 73. tRNA 79. Methionine B:Transfer RNA: The mRNA enters cytoplasm and attaches to ribosome. Translation begins at AUG, the start codon. Each tRNA has an anticodon whose bases are complementary to a codon on the mRNA strand. The ribosome positions the start codon to attract its anticodon, which is part of the tRNA that binds methionine. The ribosome also binds the next codon and its anticodon. 78. Ribosome 76. Start codon 77. mRNA Hickox: Baker Biology
The Polypeptide “Assembly Line” The ribosome joins the two amino acids—methionine and phenylalanine—and breaks the bond between methionine and its tRNA. The tRNA floats away, allowing the ribosome to bind to another tRNA. The ribosome moves along the mRNA, binding new tRNA molecules an amino acid. Translation (continued) Amino Acids Growing polypeptide chain Ribosome tRNA Phenylalanine Methionine Lysine tRNA D mRNA Completing the Polypeptide The process continues until the ribosome reaches one of the three stop codons. The result is a growing polypeptide chain. mRNA Translation direction Ribosome C Hickox: Baker Biology
Ch 11.2 The Central Idea DNA 81. Think of _________ as “Master Plan”, remaining safely in the nucleus 82. ________as the disposable “blueprints” that travel to protein building sites, the _______________ RNA RIBOSOME Genes and Proteins 83. __________contain only the instructions for assembling proteins 84.____________ determine blood type, color eyes, “everything”, rate and pattern or growth, size and shape 85.__________are key to almost everything that living cells do!!!!!! This same process occurs in every living thing from the simplest bacteria to the most complex animals. Genes proteins Proteins Hickox: Baker Biology Chapter 11.2
DNA (information storage) TRANSCRIPTION mRNA (information carrier) TRANSLATION Proteins (active cell ACTION!) Hickox: Baker Biology
Ch 11.3 Genetic Changes Gene Mutations • 86. Occasionally, there is a change in the DNA sequences. 87.Any changes in sequences are called ___________ • 88. Mutations can result in: • Proteins that work • A new trait • An offspring that survives better in environment • Mutations from outside the body: • 89. ___________: Are what causes mutations, examples are: X rays, ultraviolet light, and radioactive substances that can change the chemical nature of DNA. • 90. Sometimes mutagens can cause ___________ by cells dividing too quickly. MUTATIONS Mutagens Cancer Hickox: Baker Biology Chapter 11.3
Ch 11.3 Mutations Gene Mutations single • 91. Most mutations involve just __________ base pair, CALLED _________ mutations. • 92. Generally point mutations change ___________ amino acid in a protein. • 93. When point mutations change a nucleotide, much bigger results occur. • Example: AAGUUUGGC to AAGUUUAGC • 94. Remember: the genetic code is read in groups of three bases called __________ • 95. If there is a shift when a single nitrogenous base is added or deleted from the DNA sequence called _____________. This results in more harmful result than a point mutation. point one codons Frame shift Hickox: Baker Biology Chapter 11.3
Ch 11.3 Mutations Gene Mutations • Proteins can loose its normal function • Example: AATTAGAAATAG to ATTAGAAATAG Results: nearly every amino acid in the protein will be changed! out Chapter 11.3 Hickox: Baker Biology
Ch 11.3 Mutations Chromosomal Mutations or Abnormality CHROMOSOMAL 96.A _____________ mutation involves changes in the number of structure of chromosomes. 97. Translocation: when one chromosome breaks off and is added to a different chromosome! 97. Deletion 98.Duplication 99.Inversion Hickox: Baker Biology Chapter 11.3 100.Translocation
Ch 11.3 Mutations Gene Mutations Gene mutations results from changes in a single gene Deletion Substitution Insertion Hickox: Baker Biology Chapter 11.3