Bio Exam 4

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Bio Exam 4
2015-05-14 19:38:49

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  1. DNA
    • deoxyribonucleic acid
    • molecule that carries genetic info
    • molecule of life
    • polymer made up of nucleotides
    • have directionality
  2. genetics
    branch of biology that studies genes, heredity, and variations in living things
  3. chromosome
    structure of dna wrapped around protein
  4. inheritance
    genes carry genetic info from one generation to next
  5. nucleotide
    • monomers, make up dna
    • PO4 group + 5C sugar + nit base + OH group
    • joined together by covalent bonds between PO4 at C5 with OH at C3
    • phosphodiester bond
  6. X-ray diffraction
    • Rosalind Franklin
    • purified molecule of dna bombarded with x-rays
    • deflected x-rays make shadow of molecule
    • showed double-helix dna structure
  7. nitrogenous bases
    • at C1
    • purine: 2 rings, A, G
    • pyrimidine: 1 ring, T, C
    • paired in specific manner - purine + pyrimidine
  8. purines
    • nitrogenous base
    • 2 rings
    • A, G
  9. pyrimidines
    • nitrogenous base
    • 1 ring
    • T, C
  10. double-helix
    • 2 nucleic acid strands twisted around each other
    • held together by hydrogen bonds
    • 2 nm wide
  11. sugar-phosphate backbone
    • held together by covalent phosphodiester bonds
    • bases stick out
  12. Hydrogen bonds
    • hold bases together between strands
    • 2 bonds between A-T
    • 3 bonds between G-C
    • Weak enough to be broken by helicase
  13. antiparallel
    parallel to each other but run opposite directions
  14. complementary base pairings
    • strands are complimentary to each other due to specific base pairings
    • A-T
    • G-C
  15. DNA replication
    • Copying of DNA
    • Process of making two identical replicas from one original dna molecule
    • facilitated by enzymes
    • results in 2 new dna molecules
  16. parental strand
    • original dna strand
    • separated by helicase
    • read by dna-polymerase
    • serves as template for daughter strand
  17. daughter strand
    • new dna strand
    • complimentary to parental strand
    • put together by dna-polymerase
  18. helicase
    • enzyme that separates the parental strands during replication
    • breaks hydrogen bonds between bases
  19. DNA-polymerase
    • enzyme that reads parental strand
    • adds nucleotides by linking PO4-sugar backbone according to parental sequence
    • Sometimes adds wrong base, making mutation if not fixed
    • 1:1,000,000,000
  20. mutation
    • permanent alterations to dna's base sequence
    • point mutation: single base pair mutation
    • cancer, sickle cell anemia, disease
    • Does not always have an effect
    • Majority of DNA does not code for proteins
    • May lead to evolution
  21. What was the Hershey-Chase experiment and what were the results?
    • Used phage virus that only had DNA & protein
    • Labeled DNA & protein with different radioactive elements
    • Let phage infect bacteria to follow radioactivity
    • DNA was found inside infected cells
    • Proteins found on outside of cells
    • DNA determined to be molecule of life
  22. Describe the two types of chemical bonds that hold 1 DNA molecule together.
    • Covalent - hold PO4-sugar backbone of single strand together
    • Hydrogen - hold bases of strands together, 3 between C-G, 2 between T-A
  23. Why can we say that a DNA molecule has directionality? What is the direction in which
    a DNA sequence is read?
    • Read top to bottom, left to right
    • Molecules bonded to carbon sugars allow for directionality, will always bond to same C
  24. What are the roles of helicase and DNA-polymerase enzymes during the replication of
    1 DNA molecule?
    • Helicase separates strands
    • DNA-pol reads parent strand and builds daughter strand, also proofreads for errors
  25. When considering errors with DNA-polymerase, what are the two “fates” of the newly made DNA molecule?
    • DNA-pol proofreads the molecule and fixes the mistake
    • Keeps the mistake and causes a mutation
  26. Why does DNA replicate?
    To provide each daughter cell during mitosis and meiosis with DNA copies
  27. What is the DNA enzyme joke given in class?
    "If I were an enzyme I would be DNA helicase so I can unzip your jeans"
  28. Explain the structure of DNA. Why is this structure optimal for DNA replication?
    • Weak hydrogen bonds between bases allow helicase to separate strands
    • Stronger covalent bonds in backbone hold keep strands stable
    • 1 purine with 1 pyrimidine
  29. What are some of the effects seen after a mutation changes the Genetic Information?
    • Cancer
    • Disease, sickle cell anemia
    • Evolution
    • No effect - mutation occurs on part of DNA that does not code for protein
  30. RNA
    • communicator between dna & proteins
    • a nucleic acid
    • converts instruction from dna into codes for amino acids
    • 1 molc = 1 strand
    • made by RNA polymerase from dna
    • always 5'-3'
  31. Proteins
    • do cell's work
    • give us characteristics
    • sequence of amino acids
    • order of amino acids important
  32. Transcription
    • using dna to make rna
    • read dna instructions to assemble rna
    • same language
    • rna polymerase
    • produces t, m, r rna
  33. Translation
    • using mrna as template to assemble proteins
    • different languages
    • takes place on surface of ribosomes
    • use trna to read mrna
  34. Deoxyribose
    • DNA sugar component
    • Has H instead of OH on C2
  35. Ribose
    • RNA sugar component
    • Has OH on C2
  36. Genetic information
    • contains codons in order of bases
    • in DNA
    • used to make proteins
  37. Genes
    segments of dna with genetic info to make functional product
  38. RNA Polymerase
    • enzyme
    • moves along dna strand to make rna molc
    • add free-floating nucleotides according to order of dna bases
  39. Codon
    • words of genetic info
    • set of 3 rna nucleotides that code for an amino acid
    • 64 available codons
    • contains in mrna 
    • read by trna
  40. Anticodon
    what trna uses to read codons on mrna
  41. rRna
    • ribosomal rna
    • components of ribosomes
  42. tRNA
    • transfer rna
    • adapter between mrna & ribosomes
    • reads mrna via complimentary base pairing
    • trna for each amino acid
    • amino acid on one end, anticodon on other
  43. mRNA
    • messenger rna
    • has codes to make proteins
    • read by trna
    • template for translation
    • information from dna transcribed onto mrna
  44. Ribosome
    • made of rrna and proteins
    • where translation takes place
  45. Nonsense mutation
    • changes codon, produces STOP
    • protein ended prematurely
  46. Silent mutation
    • changes codon but still codes for correct amino acid
    • has no effect on protein
  47. Degenerate
    • More than one codon can specify for the same amino acid
    • Helps prevent mutations
  48. Missense mutation
    • change in codon results in code for different amino acid
    • makes different protein than intended
    • may lead to inherited diseases
    • sickle cell anemia
  49. What are the two main functions of DNA?
    • 1. template for replication
    • 2. genetic info for transcription & translation
    • functions contained in order of bases
  50. What are the differences between DNA and RNA?
    • 1. sugar components - deoxyribose vs ribose
    • 2. type of bases - U instead of T for rna, T has methyl H3C, U = T de-methylated 
    • 3. structure - single vs double stranded
  51. Why can we say that Transcription is like going from dictation to writing in the same language?
    • Transcription is just copying/reading the information from DNA to RNA
    • Both are nucleic acids, same biomolc, use same language
  52. What is RNA polymerase? How does it work to make a new RNA molecule?
    • Enzyme that makes rna by reading dna
    • Splits DNA like helicase, reads bases, adds comp bases to form rna strand
  53. Why does a new RNA molecule have directionality?
    • RNA always goes 5'-3'
    • Read 5-3 to determine correct codons
  54. What are the parts of a protein?
    • Amino group
    • Carboxyl group
    • R group - determine amino acids
    • has directionality - H from amino group bonds with OH from carboxyl group
  55. What are the different RNA products made from transcription?
    • mRNA - code to make protein
    • tRNA - adaptor for mRNA
    • rRNA - component of ribosome
  56. How are proteins made in the ribosomes?
    • Initiation: mRNA enters ribosome, tRNA reads AUG codon to begin process
    • Elongation: tRNA continues to read mRNA and adds amino acids to chain
    • Termination: STOP codon eventually read, protein is finished
  57. What are the different functions of the different RNA molecules in Translation?
    • mRNA contains code
    • tRNA reads code from mRNA
    • Ribosomes make the proteins from tRNA
  58. Why do cells have to regulate gene expression?
    • Prevent proteins being made when not needed
    • Conserve energy
  59. Why does the order of amino acids in a protein matter?
    • The order determines what protein is made
    • Allows for wide variety of proteins
  60. Fill in the following table comparing the cellular processes of replication and transcription:
  61. Inheritance
    • passing down traits from parents to offspring
    • aka heredity
    • genetic material passed from one generation to next
  62. Mendelian inheritance
    inheritance of traits that are defined by one gene
  63. Allele
    different version of same gene
  64. Dominant allele
    gene version that masks the other
  65. Recessive allele
    gene version that gets masked by the other
  66. Genotype
    • genetic makeup of an organism
    • genetic info present in the allele
  67. Phenotype
    • observed trait of an organism
    • trait that results from the allele
  68. Pure-breed
    • organism that always has offspring that looks like itself
    • no hybrid alleles
    • same alleles for same gene
  69. Homozygous
    • identical pairs of alleles
    • YY, yy
  70. Hybrid
    organism with two different alleles for same gene
  71. Heterozygous
    • different alleles for same gene
    • Yy
  72. Genetic cross
    experimentally mating organisms to produce offspring
  73. Self-cross
    • using only 1 organism to make offspring
    • ex: plants with both sexes
  74. Cross-breeding
    • mating 2 organisms to produce offspring 
    • ex: using 2 plants
  75. First generation
    • offspring of the P
    • F1
  76. Punnett Square
    • predict all possible outcomes of a genetic cross
    • chart segregation of alleles into gametes
    • chart all possible combinations of alleles in offsprings
  77. Who is Gregor Mendel? What was his contribution to Science?
    • Austrian monk
    • father of genetics
    • physicist & mathematician
    • performed pea plant experiments for genetics
  78. What are Mendel's two Laws?
    • Law of Segregation: alleles will be separated independently of each other into the gametes, 1 trait
    • Law of Independent Assortment: alleles of R gene segregate independently of alleles of Y gene, 2 traits
  79. Name two exceptions to Mendelian Inheritance. What are some examples?
    • Incomplete dominance: intermediate traits from dom & rec alleles, horse colors, wavy hair
    • Codominance: neither dominates nor masks, both alleles fully expressed, blood types
  80. simple trait
    • phenotypic traits controlled by single gene
    • follow Mendel's laws
    • direct relationship between phenotype & genotype
    • dom & rec alleles
  81. complex traits
    • phenotype affected by many genes on different chromosomes
    • also influenced by enviro factors
    • do not follow mendelian inheritance
    • ex: human height & body fat affected by genes & diet
  82. autosomal chromosomes
    chroms 1-22
  83. sex-linked chromosomes
    • chrom 23
    • X has over 1,000 genes
    • Y has 24 genes
    • X & Y share 9 genes
    • Male X alleles will be expressed, no other X to mask
  84. frame shift mutation
    • changes the reading frame
    • add or subtract an extra base
  85. pedigree
    • record of ancestry to study family lines
    • analyse human traits
    • determine pattern of inheritance
  86. carrier
    • person with recessive allele but does not show trait
    • passes on to offspring
  87. karyotype
    • complete human genome
    • diagram of all chromosomes
    • determine sex, disease, mutation
  88. X-Linked Dominant Pattern
    • dom allele on X chrom
    • affected males always pass to daughters
    • affected females can pass equally to daughters/sons
    • more common in girls, can receive from both parents
    • males only receive from mom
    • ex: wolfman
  89. X-Linked Recessive Pattern
    • males more affected than females, males only have 1 X, cannot mask
    • affected male received from mother
    • carrier usually mother
    • affected girls received both rec X alleles from both parents
    • ex: color blindness, hemophilia
  90. Autosomal Dominant pattern
    • dominant alleles in genes of chroms 1-22
    • no carriers
    • every generation affected
    • homo more affected
    • males/females affected equally
    • 50% having affected child
    • mild or get later in life
    • ex: huntington's disease
  91. Autosomal recessive pattern
    • rec alleles in chrom 1-22
    • affected ppl must have both rec alleles to show
    • no prior history of trait in family
    • parent of affected kid are unaffected carriers
    • 25% chance of having affected offspring
    • males/females affected equally
    • ex: sickle cell anemia
  92. Examples of Human Simple Traits
    • roll tongue
    • grey hair
    • free earlobes
    • widow's peak
    • normal thumb
    • dimples
    • cleft chin
    • right-handed
  93. What are the genome mutations?
    • Aneuploidy: abnormal number of chromosomes
    • Trisomy: Extra chromosome 
    •  - 21 = down syn
    •  - 18 = Patau's syn
    •  - 13 = Edwards syn
    • Monosomy: Missing chromosome
    • Polyploidy: Complete extra set (69 chroms), fatal
  94. Theory of Evolution
    • explains the slow progression that resulted in great diversity of life
    • does not try to explain how life began
    • many lines of evidence from genetics, fossils, morphology
  95. Evolution
    • process of slow growth or development
    • Change in the inherited traits of biological populations over successive generations
    • Passing mutations down through populations over time
  96. What is Evolution? Be able to dissect and describe the parts that make up the accepted definition of Evolution.
    • Change: mutations in DNA
    • Inherited traits: passing genes from parent to offspring
    • Populations: all members of species in defined area
    • Generations: requires time
  97. What happens when a new allele gives an advantage for survival?
    Allele can be passed down
  98. What happens when a new allele gives a disadvantage for survival?
    • Allele not passed down
    • Parent dies before reproducing
  99. Who is Lamarck and what was his explanation for the observed changes in organisms? What is his Theory of Evolution? Why is his theory wrong?
    • French naturalist
    • Studied and classified animals and plants
    • first to study evolution
    • first to use word "biology"
    • Theory of Inheritance of Acquired Traits
    • Species change over time in response to their enviro
    • Giraffe neck example
    • New adaptation would be passed to offspring
    • Wrong about how changes occur
    • Mice tail example
  100. Who is Darwin and what was his explanation for the observed changes in organisms? What is his Theory of Evolution?
    • English naturalist
    • 5 year voyage around world, observed geographic distributions of animals and fossils
    • Theory of Natural Selection
    • common ancestry
    • desirable traits favored for reproduction
  101. Survival of the Fittest
    • H. Spencer
    • After reading Darwin's book
  102. Provide real-life examples of Natural Selection and how it affects the frequency of alleles in a population. In lecture, we discussed examples of tigers, beetles and moths.
    • Favorable = more frequent
    • Unfavorable = less frequent
    • Crows eat green beetles and leave brown
    • White tigers blend into snow better than orange
    • Moths adapted to darker colors of trees after industrial rev
  103. Homologous structures
    structures that do different jobs but have common ancestor
  104. What are different lines of evidence that support the Evolution Theory?
    • Fossil records: preserved remains showing existence and extinction of various species, can compare skeletons from time periods in specific locations, evolution of horse shows common ancestor with rhino
    • Comparative morphology and embrology: common occurrence of homologous structures in different organisms, gills and tails in embryos show common ancestor
  105. biotechnology
    • Use of organisms to make useful products
    • cultivation
    • selective breeding
    • fermentation
    • genetic engineering
    • forensic bio
  106. cloning
    • making more of something
    • make many copies from small start
    • ex - human insulin
  107. transgenic
    moving genetic material from one organism to another
  108. GMO's
    • genetically modified organisms
    • transgenic tech allows organisms to make new products
    • questions ppl ask: ethical, safe, money
  109. selective breeding
    • humans breeding animals and plants for specific traits
    • enabled cultivation from single ancestor
    • crops and domesticated animals
    • mustard plant: kale, broccoli, cauliflower, brussel sprouts
  110. forensics
    • solving crimes
    • using biology to identifying individuals
    • examining past information
    • prepare DNA profiles
  111. STR's
    • short tandem repeats
    • small sequences of bases that repeat in a row
    • usually 4 bases long
    • repeat 6-40 times per person in row
    • 15 STR's used for DNA profiling
    • 13 auto, 2 sex
    • 2 alleles, one from each parent
    • can be hetero or homo
  112. Name and describe examples of biotechnology
    • Agriculture: cultivation of plants & animals, earliest biotech enterprise, dominant means of food, allowed settlement
    • Selective breeding: breeding plants and animals for specific traits
    • Fermentation: convert glucose to acid, alcohol, gases, make food, drinks, products
    • Antibiotics: anti-microbial compounds from living organisms, Penicillin
    • Genetic engineering: food
    • Forensic biology: solving crimes
  113. How can we produce a human gene product (e.g. insulin) in massive amounts using bacteria and cloning techniques?
    • Cut the gene of interest from the human cell
    • Insert into plasmid from bacteria to make recombinant plasmid
    • Insert plasmid back into bacteria to produce many bacteria cells with new ability
  114. What is Forensic Biology?
    • Solving crimes
    • Identifying individuals
    • examining info from the past
  115. How can we use STR’s to identify criminals or assign paternity?
    • Create DNA profile using STR's
    • Compare DNA profiles to find matches