dog breeds. question of the day feb 11 normal human zygote cells contain normal human zygote cells...

Dog BreedsDog Breeds

Question of the Day Feb 11Question of the Day Feb 11

Normal human zygote cells containNormal human zygote cells contain

A. 23 chromosomesA. 23 chromosomes B. 44 chromosomes and an X and YB. 44 chromosomes and an X and Y C. 46 chromosomesC. 46 chromosomes D. 44 chromosomesD. 44 chromosomes

AGENDA Feb 11AGENDA Feb 11

Big Question: What is a karyotype?Big Question: What is a karyotype?

1. Question of the Day1. Question of the Day 2. Introduction to Chapter 142. Introduction to Chapter 14 3. Karyotyping3. Karyotyping 4. Review and Homework4. Review and Homework

– Complete Lab and Discussion QuestionsComplete Lab and Discussion Questions

Chapter 14: Chapter 14:

The HumanThe Human

GenomeGenome

14-1: Human Heredity14-1: Human HeredityHow many chromosomes does an adult How many chromosomes does an adult human cell contain?human cell contain?

Autosomes – any chromosomes that are Autosomes – any chromosomes that are not sex chromosomes.not sex chromosomes.

Sex Chromosomes – X and Y chromosomes Sex Chromosomes – X and Y chromosomes that determine sex of individual.that determine sex of individual.

Normal Individuals represented asNormal Individuals represented as

Males Males 46, XY 46, XY

Females Females 46, XX 46, XX

Solve a Punnett Square to predict sex of offspringSolve a Punnett Square to predict sex of offspring

Human CellHuman Cell 22 pairs of 22 pairs of

homologous homologous chromosomeschromosomes– called autosomescalled autosomes

1 pair of sex 1 pair of sex chromosomeschromosomes– 2323rdrd pair pair

egg, spermegg, sperm– half the number of half the number of

chromosomeschromosomes– egg carries an x, egg carries an x,

sperm carries a y sperm carries a y or xor x

KaryotypeKaryotype a picture of a picture of chromosomes chromosomes that is laid out that is laid out with with homologous homologous chromosomes chromosomes paired.paired.

Numbered 1-23 Numbered 1-23 in order of sizein order of size

What does the What does the size of the size of the chromosome chromosome indicate?indicate?

Question of the DAY Feb Question of the DAY Feb 1212

Which statement is not true regarding Which statement is not true regarding homologous chromosomes?homologous chromosomes?

A. Specific genes are found at the same A. Specific genes are found at the same locuslocus

B. They have the same sizeB. They have the same size C. Genes will express identical traitsC. Genes will express identical traits D. They are joined at the same D. They are joined at the same

centromere locationscentromere locations


Big Question: How is a pedigree used Big Question: How is a pedigree used to predict the occurrence of genetic to predict the occurrence of genetic disorders?disorders?

1. Question of the Day1. Question of the Day 2. 14-1 Notes2. 14-1 Notes 3. Pedigree Practice Problems3. Pedigree Practice Problems 4. Review and Homework4. Review and Homework

– Complete Lab and Discussion QuestionsComplete Lab and Discussion Questions– DUE THURSDAY (YES… we will be DUE THURSDAY (YES… we will be

here).here).

Genes and the EnvironmentGenes and the Environment

All of our inherited characteristics are All of our inherited characteristics are governed by our genes.governed by our genes.– Many traits are polygenic.Many traits are polygenic.

Other factors influence our Other factors influence our phenotypes.phenotypes.– Nutrition and ExerciseNutrition and Exercise

Average height has increased Average height has increased 10 cm 10 cm in the last 200 years in the last 200 years 3.93 inches3.93 inches– U.S. and EuropeU.S. and Europe

Blood Group GenesBlood Group Genes

How many different alleles control How many different alleles control blood type?blood type?

How is blood type expressed?How is blood type expressed?

How many different blood types are How many different blood types are there?there?

Blood Group GenesBlood Group Genes

Rh blood groupsRh blood groups

Positive (+)Positive (+) Negative Negative (-)(-)

Rh+/Rh+ or Rh+/Rh- Rh+/Rh+ or Rh+/Rh- Rh-/Rh- Rh-/Rh- Blood Type AB- Blood Type AB-

A allele and B allele + 2 Rh- allelesA allele and B allele + 2 Rh- alleles

Alleles Figure 14-6Alleles Figure 14-6

Dominant – Some genetic disorders Dominant – Some genetic disorders are expressed through these allelesare expressed through these alleles– Only requires one alleleOnly requires one allele

Recessive – Most genetic disorders Recessive – Most genetic disorders are transmitted through these allelesare transmitted through these alleles

Codominant – Sickle Cell DiseaseCodominant – Sickle Cell Disease

Pedigree AnalysisPedigree Analysis rely on family rely on family

histories and histories and medical records medical records to study humansto study humans

pedigree:pedigree: diagram that diagram that follows the follows the inheritance of a inheritance of a single trait single trait through several through several generationsgenerations


Big Question: How is a pedigree used Big Question: How is a pedigree used to predict the occurrence of genetic to predict the occurrence of genetic disorders?disorders?

1. Question of the Day1. Question of the Day 2. Pedigree Practice Problems2. Pedigree Practice Problems 3. Review and Homework3. Review and Homework

– HAND IN LABSHAND IN LABS

Pedigrees record and trace the Pedigrees record and trace the occurrences of traits within a family.occurrences of traits within a family.

British Royal FamilyBritish Royal Family

The Story of AnastasiaThe Story of Anastasia

DO NOWDO NOW

Explain why males cannot be carriers Explain why males cannot be carriers for sex-linked disorders.for sex-linked disorders.

DO NOW Feb 18DO NOW Feb 18

A mother (type AB blood) and a A mother (type AB blood) and a father (type A blood) have two father (type A blood) have two children. What are the possible children. What are the possible genotypes of the children. Show all genotypes of the children. Show all possible combinations. Solve Punnett possible combinations. Solve Punnett Squares to support your answer.Squares to support your answer.

DO NOW ANSWEREDDO NOW ANSWERED

Sex-linked inheritance is directly connected Sex-linked inheritance is directly connected to the X-chromosome. Males only have one to the X-chromosome. Males only have one X-chromosome and will always express this X-chromosome and will always express this type of trait/disorder.type of trait/disorder.

Females have two X-chromosomes. Women Females have two X-chromosomes. Women only carrying one allele for the only carrying one allele for the trait/disorder are carriers. Recessive trait/disorder are carriers. Recessive traits/disorders will not be expressed unless traits/disorders will not be expressed unless both X-chromosomes carry the allele. both X-chromosomes carry the allele.


Big Question: What is Sex-linked Big Question: What is Sex-linked Inheritance?Inheritance?

1. DO NOW1. DO NOW 2. Chapter 13 Tests2. Chapter 13 Tests 3. Sex-linked Inheritance3. Sex-linked Inheritance 4. Review and Homework4. Review and Homework

14-2: Sex-linked Inheritance14-2: Sex-linked Inheritance sex determinationsex determination

– XX femaleXX female– XY maleXY male

sex-linked genes:sex-linked genes: genes located on the genes located on the sex chromosomessex chromosomes– almost always on almost always on

the X chromosomethe X chromosome– Y chromosome Y chromosome

contains a few contains a few genes for male genes for male developmentdevelopment

Sex-linked InheritanceSex-linked Inheritance any X chromosome-linked gene a male inherits is any X chromosome-linked gene a male inherits is

expressed, since they only have oneexpressed, since they only have one gets passed from father to daughters, then gets passed from father to daughters, then

daughters to their sonsdaughters to their sons examples are hemophilia, colorblindness, examples are hemophilia, colorblindness,

Duchenne’s muscular dystrophyDuchenne’s muscular dystrophy

Human Genetic DisordersHuman Genetic Disorders autosomal genetic autosomal genetic

disordersdisorders– albinismalbinism

recessive allele on recessive allele on chromosome 11chromosome 11

can’t produce can’t produce melaninmelanin

– cystic fibrosiscystic fibrosis recessive allele on recessive allele on

chromosome 7chromosome 7 heavy mucus clogs heavy mucus clogs

lungs and breathing lungs and breathing passagewayspassageways

DO NOW Feb 19DO NOW Feb 19 Perform the following dihybrid cross.Perform the following dihybrid cross.

A homozygous long mane lion that is A homozygous long mane lion that is heterozygous for a loud roar mates with a heterozygous for a loud roar mates with a lioness with a heterozygous long mane and a lioness with a heterozygous long mane and a soft roar.soft roar.

What are the chances that one of the cubs will What are the chances that one of the cubs will have a homozygous long mane and a soft roar?have a homozygous long mane and a soft roar?

List all of the possible genotype and phenotype List all of the possible genotype and phenotype ratios.ratios.

AGENDA Feb 19AGENDA Feb 19 Big Question: What is Sex-linked Big Question: What is Sex-linked

Inheritance?Inheritance? 1. DO NOW1. DO NOW 2. Review selected HW problems2. Review selected HW problems 3. Chapter 13 Tests3. Chapter 13 Tests 4. More Genetic Disorders4. More Genetic Disorders 5. The Human Genome Project5. The Human Genome Project 6. Review and Homework6. Review and Homework

– Read Section 14-2 Details of Genetics Read Section 14-2 Details of Genetics DisordersDisorders

tay sachstay sachs– recessive allele recessive allele

on chromosome on chromosome 1515

– suffer from suffer from breakdown of the breakdown of the nervous systemnervous system

sickle cell diseasesickle cell disease– recessive allele on recessive allele on

chromosome 11chromosome 11– produces an alternate produces an alternate

form of hemoglobin form of hemoglobin that causes the red that causes the red blood cells to become blood cells to become a sickle shapea sickle shape

– one DNA base one DNA base changedchanged

– Glutamic acid for Glutamic acid for ValineValine

Sickle Cell DiseaseSickle Cell Disease Allele very prominent in African AmericansAllele very prominent in African Americans

– Carried by many individualsCarried by many individuals Connected to malaria – a parasitic disease Connected to malaria – a parasitic disease

that affects red blood cellsthat affects red blood cells

Individuals who are heterozygous for sickle Individuals who are heterozygous for sickle cell are resistant to malariacell are resistant to malaria

When body destroys sickled cells, parasite When body destroys sickled cells, parasite causincausing malaria also destroyed.g malaria also destroyed.– Low oxygen = sickle shape = cells clump Low oxygen = sickle shape = cells clump

togethertogether

PKU: PKU: phenylketonuriaphenylketonuria– recessive allele on recessive allele on

chromosome 12chromosome 12– causes mental causes mental

retardationretardation

Huntington’s diseaseHuntington’s disease– dominant allele on dominant allele on

chromosome 4chromosome 4– lose muscle lose muscle

control and control and nervous system nervous system breaks downbreaks down

AGENDAAGENDA

Big Question: What is Sex-linked Big Question: What is Sex-linked Inheritance?Inheritance?

1. DO NOW1. DO NOW 2. Sex-linked Inheritance Section 7-22. Sex-linked Inheritance Section 7-2 3. Pedigree Practice3. Pedigree Practice 4. Closing Thoughts4. Closing Thoughts HAND IN YOUR KARYOTYPE LABSHAND IN YOUR KARYOTYPE LABS

Chromosome Number Chromosome Number DisordersDisorders

occurs by occurs by nondisjunctionnondisjunction: when : when abnormal number of chromosomes are abnormal number of chromosomes are produced in the sex cells due to them not produced in the sex cells due to them not separating correctlyseparating correctly

Turner’s SyndromeTurner’s Syndrome either a sperm or an egg is either a sperm or an egg is

produced without a sex produced without a sex chromosomechromosome

XO genotypeXO genotype– O means sex chromosome O means sex chromosome

is missingis missing

sex organs are not sex organs are not fully developedfully developed

can not have childrencan not have children only in femalesonly in females

Klinefelter SyndromeKlinefelter Syndrome

have an extra X have an extra X chromosomechromosome– XXY genotypeXXY genotype

causes mental causes mental retardationretardation

can not reproducecan not reproduce only in malesonly in males

Down SyndromeDown Syndrome

trisomytrisomy 21 21– means 3 copies of means 3 copies of

chromosome #21chromosome #21

causes heart and causes heart and circulatory circulatory problems, mental problems, mental retardation, and a retardation, and a weakened immune weakened immune systemsystem

Other Causes of DisordersOther Causes of Disorders

deletionsdeletions: can occur : can occur from pieces of from pieces of chromosomes chromosomes breaking off and breaking off and getting lost in meiosisgetting lost in meiosis

translocationtranslocation: when : when pieces of pieces of chromosomes break chromosomes break off and become off and become reattached to another reattached to another

Prenatal DiagnosisPrenatal Diagnosis want to detect if want to detect if

unborn child will unborn child will have a disorderhave a disorder

two waystwo ways– amniocentesisamniocentesis: :

withdraw fluid withdraw fluid from sac around from sac around fetusfetus

– chorionic villus chorionic villus samplingsampling: tissue : tissue surrounding fetus surrounding fetus is removed and is removed and examinedexamined

Special Topics Special Topics in Human in Human GeneticsGenetics

barr body: barr body: dense dense region in the nucleus of region in the nucleus of most cells in human most cells in human femalesfemales

condensed turned-off X condensed turned-off X chromosomechromosome

not found in males not found in males because their one X because their one X chromosome is activechromosome is active

happens in some happens in some tissues and in some tissues and in some cellscells


Big Question: What is the Human Big Question: What is the Human Genome Project?Genome Project?

1. CHAPTER 14 Problem Solving Test1. CHAPTER 14 Problem Solving Test 2. Complete Chapter 14-3 Notes2. Complete Chapter 14-3 Notes 3. Begin to Study for T2 Exam3. Begin to Study for T2 Exam

14-3 Testing for Alleles14-3 Testing for Alleles

DNA probes – specific DNA base DNA probes – specific DNA base sequences that detect the sequences that detect the complementary base sequences complementary base sequences found in disease causing allelesfound in disease causing alleles

Cystic Fibrosis and Tay Sachs are Cystic Fibrosis and Tay Sachs are examples that use DNA probes. examples that use DNA probes.

DNA FingerprintingDNA Fingerprinting

RepeatsRepeats are specific sequences of are specific sequences of DNA unique to every individualDNA unique to every individual– Do not code for proteinsDo not code for proteins

Repeats cut with restriction enzymesRepeats cut with restriction enzymes Gel electrophoresis separates Gel electrophoresis separates

fragmentsfragments Labeled with radioactive probesLabeled with radioactive probes Forensics, detection of inherited Forensics, detection of inherited

diseases, and paternity casesdiseases, and paternity cases

Human Genome ProjectHuman Genome Project Human genome sequencing completed in 2003.Human genome sequencing completed in 2003.

Included sequencing of other organisms including E. Included sequencing of other organisms including E. coli, multiple strains of yeast, the fruit fly, the coli, multiple strains of yeast, the fruit fly, the mosquito, the honey bee, the cow, the dog, the mosquito, the honey bee, the cow, the dog, the horse, and the rat.horse, and the rat.

At least 18 countries have established human At least 18 countries have established human genome research programs.genome research programs.

Australia, China, Germany, Italy, Russia, Sweden, and Australia, China, Germany, Italy, Russia, Sweden, and the United Kingdom are among the nations involved the United Kingdom are among the nations involved in the Human Genome Organization which in the Human Genome Organization which coordinates international collaboration.coordinates international collaboration.

Gene TherapyGene Therapy Replacement of an absent or faulty Replacement of an absent or faulty

gene with a normal working gene.gene with a normal working gene.

Gene TherapyGene Therapy

DO NOW Feb 19DO NOW Feb 19

Explain how autosomal recessive Explain how autosomal recessive disorders are passed down from disorders are passed down from parent to offspring.parent to offspring.

DO NOW ANSWEREDDO NOW ANSWERED

Autosomal recessive disorders require Autosomal recessive disorders require both parents to have at least one allele both parents to have at least one allele for the disorder. Each parent must then for the disorder. Each parent must then pass this recessive allele on to their pass this recessive allele on to their child.child.

The genotype for a child with a recessive The genotype for a child with a recessive disorder of this type is aa, ee, tt, etc.disorder of this type is aa, ee, tt, etc.

Both alleles are recessive (lower-case)Both alleles are recessive (lower-case)

dog breeds. question of the day feb 11 normal human zygote cells contain normal human zygote cells...

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