Heredity (B) -2014 Heredity (B) -2014

KAREN LANCOURKAREN LANCOUR HEREDITY HEREDITY

NATIONAL SUPERVISORNATIONAL SUPERVISORkarenlancour@charter.net

Event Rules – 2014 Event Rules – 2014

DISCLAIMERDISCLAIMERThis presentation was prepared This presentation was prepared using draft rules.  There may be using draft rules.  There may be some changes in the final copy of the some changes in the final copy of the rulesrules.  .  The rules which will be in your The rules which will be in your Coaches Manual and Student Coaches Manual and Student Manuals will be the official rules.Manuals will be the official rules.

Event Rules – 2014 Event Rules – 2014

BE SURE TO CHECK THE BE SURE TO CHECK THE 2014 EVENT RULES 2014 EVENT RULES FOR FOR EVENT PARAMETERS AND EVENT PARAMETERS AND TOPICS FOR EACH TOPICS FOR EACH COMPETITION LEVELCOMPETITION LEVEL

TRAINING MATERIALSTRAINING MATERIALS Training Power Point Training Power Point – content overview– content overview Training Handout Training Handout - content information- content information Sample Tournament Sample Tournament – sample problems with key – sample problems with key Event Supervisor Guide Event Supervisor Guide – prep tips, event needs, – prep tips, event needs,

and scoring tips and scoring tips Internet Resource & Training CD’s Internet Resource & Training CD’s – on the – on the

Science Olympiad website at Science Olympiad website at www.soinc.org under under Event InformationEvent Information

Biology-Earth Science CDBiology-Earth Science CD,, Genetics CD (updated) Genetics CD (updated) for Heredity and Designer Genes as well as the for Heredity and Designer Genes as well as the Division B and Division C Test PacketsDivision B and Division C Test Packets are are available from SO store atavailable from SO store at www.soinc.org

Heredity Heredity (B)(B)

Content Basic principles of genetics Some possible areas – dominant,

recessive, incomplete dominance, co-dominance, monohybrid & dihybrid crosses, test cross, multiple alleles, sex-linkage, genotype, phenotype, epistasis, mutations, multifactorial traits, pedigrees, karyotypes, mitosis, meiosis, nondisjunction, genetic disorders, DNA structure and replication, transcription, translation, common genetic disorders

Process Skills – data analysis, predictions, calculations, inferences, observations

Possible Topics for Various Levels

Regional & State Regional & State National (all topics)

Monohybrid crossMonohybrid cross Dihybrid crossDihybrid cross Pedigree construction and Pedigree construction and analysis analysis

Dominant and recessive Dominant and recessive allelesalleles

Sex-linked traitsSex-linked traits Production of gametes with Production of gametes with Abnormal #’s of Abnormal #’s of chromosomeschromosomes

Genotype vs. phenotypeGenotype vs. phenotype Pedigree analysis Pedigree analysis Trihybrid cross (probability Trihybrid cross (probability analysis)analysis)

Human sex determinationHuman sex determination Multiple allelesMultiple alleles Analysis of karyotypes for Analysis of karyotypes for deletion,deletion,

addition, translocationaddition, translocation

Gene: protein relationshipGene: protein relationship DNA structure & DNA structure & replicationreplication

Transcription and translation Transcription and translation

Mitosis Mitosis Meiosis and gamete Meiosis and gamete formationformation

Multifactorial traits Multifactorial traits

Human karyotypes analysis Human karyotypes analysis for nondisjunction for nondisjunction disordersdisorders

Co-dominance &Co-dominance &Incomplete Dominance Incomplete Dominance

EpistasisEpistasis

PRINCIPLES OF PRINCIPLES OF GENETICS GENETICS GENESGENES – come in pairs – come in pairs

Section of DNA – codes protein or part of Section of DNA – codes protein or part of protein protein

One from each parent One from each parent

ALLELEALLELE – different forms of a gene – different forms of a gene MULTIPLE ALLELES MULTIPLE ALLELES – more than 2 – more than 2

forms of a gene forms of a gene HOMOZYGOUSHOMOZYGOUS – same alleles– same alleles HETEROZYGOUSHETEROZYGOUS – different alleles– different alleles

Dominant vs. Recessive Dominant vs. Recessive Dominant Dominant –– always always

expressed expressed Capital letters – Capital letters – NN Homozygous - Homozygous - NNNN Heterozygous - Heterozygous - NNnn

Recessive Recessive –– prevented prevented by dominantby dominant Lower case letters – Lower case letters – nn Homozygous – Homozygous – nnnn

Punnett Square – Punnett Square – Box showingBox showingallele combinations allele combinations

Dominant and Dominant and RecessiveRecessive Autosomal DominantAutosomal Dominant

Dominant gene on an autosomeDominant gene on an autosome Autosomal RecessiveAutosomal Recessive

Recessive gene on an autosome Recessive gene on an autosome Sex-linked DominantSex-linked Dominant

Dominant gene on a sex chromosomeDominant gene on a sex chromosome Sex-linked RecessiveSex-linked Recessive

Recessive gene on a sex chromosomeRecessive gene on a sex chromosome

Monohybrid Cross Monohybrid Cross

HybridHybrid – Ss– Ss X SsX Ss

One TraitOne Trait – Smooth vs – Smooth vs wrinkled wrinkled

Two gametes per Two gametes per parentparent

S and s S and s

Punnett SquarePunnett Square with with 4 boxes – 4 4 boxes – 4 offspringoffspring

Genotype & Phenotype Genotype & Phenotype

GenotypeGenotype      PhenotypePhenotype

  SS or Ss Round SS or Ss Round

ss Wrinkledss Wrinkled

Genotype frequencyGenotype frequency

1:2:1 1:2:1

Phenotype frequencyPhenotype frequency

3:1 3:1

DihybridDihybrid Cross Cross

Dihybrid Dihybrid – 2 traits – 2 traits

Gametes per parentGametes per parent = 4= 4

Punnett SquarePunnett Square – 16 – 16 boxes boxes

Genotype ratioGenotype ratio

1:2:1:2:4:2:1:2:11:2:1:2:4:2:1:2:1

Phenotype ratioPhenotype ratio

9:3:3:1 9:3:3:1

Trihybrid Cross Trihybrid Cross

Incomplete DominanceIncomplete Dominance HybridHybrid is a blend of is a blend of

two traitstwo traits Genotype Genotype

frequencyfrequency

1:2:11:2:1 Phenotype Phenotype

frequencyfrequency

1:2:11:2:1 ExamplesExamples::

Flowers, Animal furFlowers, Animal fur

Co-dominance Co-dominance More than one dominant More than one dominant

alleleallele Blood types – Blood types – A,B,O allelesA,B,O alleles Phenotypes GenotypesPhenotypes Genotypes

A A I I A AII A A or or II A Ai i

B IB IBBIIB B or Ior IBBii

AB AB I I A AIIBB

O O ii ii

Co-dominance

co-dominanceco-dominance – both dominant alleles (genes) in an individual are – both dominant alleles (genes) in an individual are expressed as blood typesexpressed as blood types

A and B genes are co-dominant and both dominant over the O A and B genes are co-dominant and both dominant over the O gene which is recessive gene which is recessive

ABO Blood System ABO Blood System

Independent Independent Assortment Assortment vs. vs. Linkage Linkage

Independent AssortmentIndependent Assortment – genes on – genes on different chromosomes separate different chromosomes separate independently during meiosisindependently during meiosis

LinkageLinkage – genes on the same – genes on the same chromosome are inherited as a groupchromosome are inherited as a group Autosomal linkageAutosomal linkage – on – on

autosomesautosomes Sex-linkedSex-linked – on sex chromosomes– on sex chromosomes

Linkage – Sex LinkageLinkage – Sex Linkage

LinkageLinkage – genes on the same – genes on the same chromosome inherited as a groupchromosome inherited as a group

Sex-linkageSex-linkage – genes on sex – genes on sex chromosomes (esp. X)chromosomes (esp. X)

Y-chromosome shorterY-chromosome shorter – – some some genes from X missinggenes from X missing

X-linked traitsX-linked traits more common in more common in menmen

Men get X-chromosome from mom Men get X-chromosome from mom Red-green colorblindness, Red-green colorblindness,

hemophiliahemophilia

Environmental Environmental influence on genes influence on genes expression expression

Gene function Gene function is influenced by is influenced by environment as with identical twins environment as with identical twins

Genes Genes have blueprint for proteins or have blueprint for proteins or parts of proteinsparts of proteins

Proteins Proteins can be structural proteins can be structural proteins (parts of body) or functional (parts of body) or functional proteins (hormones/enzymes)proteins (hormones/enzymes)

Epistasis and Epistasis and Multifactorial Multifactorial Inheritance Inheritance

EpistasisEpistasis - the interaction between - the interaction between two or more genes to control a single two or more genes to control a single phenotypephenotype

Multifactorial inheritanceMultifactorial inheritance - many - many factors (multifactorial) both genetic factors (multifactorial) both genetic and environmental are involved in and environmental are involved in producing the trait or condition. producing the trait or condition. Examples: Examples: height, weight, cleft height, weight, cleft palate, spina bifida palate, spina bifida

Pedigree Symbols Pedigree Symbols

GenerationsGenerations = I – Original Parents, II- F1 (children), III – F2 (grandchildren)

Pedigree – Curly vs Pedigree – Curly vs Straight Hair Straight Hair

Types of AnalysisTypes of Analysis Relationships Relationships Dominant GeneDominant Gene – H – H

CurlyCurly Recessive GeneRecessive Gene – h – h

Straight Straight Genotypes Genotypes PhenotypesPhenotypes

KaryotypesKaryotypes Pairs 1-22Pairs 1-22

=Autosomes =Autosomes XYXY = Sex chromosomes= Sex chromosomes MaleMale = X & Y= X & Y FemaleFemale = only X= only X NondisjunctionNondisjunction Extra chromosomesExtra chromosomes

(Trisomy)(Trisomy) Missing Missing

chromosomeschromosomes(Monosomy)(Monosomy)

Cell Cycle Cell Cycle

InterphaseInterphase G1G1 S – DNA S – DNA

replicatesreplicates G2G2

MitosisMitosis ProphaseProphase MetaphaseMetaphase AnaphaseAnaphase Telophase Telophase

Mitosis vs Meiosis Mitosis vs Meiosis

MitosisMitosis Growth and Asexual ReproductionGrowth and Asexual Reproduction One division – 2 diploid cells One division – 2 diploid cells Genetically same as originalGenetically same as original

MeiosisMeiosis Gametes for Sexual ReproductionGametes for Sexual Reproduction 2 divisions – 4 haploid cells2 divisions – 4 haploid cells

DNA Structure DNA Structure Double helix Double helix Antiparallel Antiparallel – 3’ to – 3’ to

5’5’ NucleotideNucleotide

Deoxyribose sugarDeoxyribose sugar PhosphatePhosphate Nitrogen basesNitrogen bases

AdenineAdenine ThymineThymine GuanineGuanine CytosineCytosine

DNA DNA Replication Replication

ReplicationReplication (in (in nucleus) nucleus)

DNADNA uncoils & uncoils & splitssplits

ReadsReads 3’ to 5’ 3’ to 5’ AssemblesAssembles 5’ to 3’ 5’ to 3’ 4 types4 types of of

nucleotidesnucleotides OkazakiOkazaki fragments fragments

Types of RNA Types of RNA

Differences between DNA & RNADifferences between DNA & RNA Single strandSingle strand Ribose instead of DeoxyriboseRibose instead of Deoxyribose Uracil instead of ThymineUracil instead of Thymine

Messenger RNAMessenger RNA – carries blueprint– carries blueprint Transfer RNATransfer RNA – brings amino acids– brings amino acids Ribosomal RNARibosomal RNA – reads code– reads code

Transcription & Transcription & TranslationTranslation

TranscriptionTranscription – makes RNA (in – makes RNA (in nucleus)nucleus)

Translation (protein synthesis) Translation (protein synthesis) --Reads blueprint and makes Reads blueprint and makes protein or part of protein (in protein or part of protein (in cytoplasm at the cytoplasm at the

ribosome)ribosome)

Transcription of RNA Transcription of RNA from DNAfrom DNA

Transcription: Transcription: Synthesis of RNA from a DNA Template. Synthesis of RNA from a DNA Template. Requires DNA-dependent RNA polymerase plus the Requires DNA-dependent RNA polymerase plus the

four nucleotides (ATP, GTP. CTP and UTP). four nucleotides (ATP, GTP. CTP and UTP). Synthesis begins at a the initiation site on DNA Synthesis begins at a the initiation site on DNA The template strand is read 3' to 5' and the mRNA is The template strand is read 3' to 5' and the mRNA is

synthesized 5' to 3' synthesized 5' to 3'

Translation – Protein Translation – Protein Synthesis Synthesis

Mutations Mutations

MutationMutation – any change in the – any change in the DNADNA

Gene mutationGene mutation Chromosomal mutationChromosomal mutation Agents causing mutationsAgents causing mutations – –

radiation, chemicals, excess radiation, chemicals, excess heat heat