1 / 58

Section 1: Basic Patterns of Human Inheritance

Chapter 11 Complex Inheritance and. Human Heredity. Section 1: Basic Patterns of Human Inheritance. Section 2: Complex Patterns of Inheritance. Section 3: Chromosomes and Human Heredity Do you look like you mom or dad? Why? Did you inherit more traits from one parent?.

lefty
Télécharger la présentation

Section 1: Basic Patterns of Human Inheritance

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 11 Complex Inheritance and Human Heredity Section 1: Basic Patterns of Human Inheritance Section2: Complex Patterns of Inheritance Section 3: Chromosomes and Human Heredity Do you look like you mom or dad? Why? Did you inherit more traits from one parent?

  2. Complex Inheritance and Human Heredity Chapter 11 Human genetics Recessive Genetic Disorders • A recessive trait is expressed when the individual is homozygous recessive for the trait. Protein is not made!

  3. Complex Inheritance and Human Heredity Chapter 11 11.1 Basic Patterns of Human Inheritance Cystic Fibrosis • Affects the mucus-producing glands, digestive enzymes, and sweat glands • Chloride ions are not absorbed into the cells of a person with cystic fibrosis but are excreted in the sweat. • Without sufficient chloride ions in the cells, a thick mucus is secreted.

  4. The Cause of Cystic Fibrosis Chromosome # 7 CFTR gene The most common allele that causes cystic fibrosis is missing 3 DNA bases. As a result, the amino acid phenylalanine is missing from the CFTR protein. Normal CFTR is a chloride ion channel in cell membranes. Abnormal CFTR cannot be transported to the cell membrane. The cells in the person’s airways are unable to transport chloride ions. As a result, the airways become clogged with a thick mucus.

  5. Complex Inheritance and Human Heredity Chapter 11 11.1 Basic Patterns of Human Inheritance Albinism • Caused by altered genes (epistasis), resulting in the absence of the skin pigment melanin in hair and eyes. • White hair • Very pale skin • Pink pupils

  6. Complex Inheritance and Human Heredity Chapter 11 11.1 Basic Patterns of Human Inheritance Tay-Sachs Disease • Caused by the absence of the enzymes responsible for breaking down fatty acids called gangliosides found mostly in “European” Jews. • Gangliosides accumulate in the brain, inflating brain nerve cells and causing mental deterioration and death.

  7. Complex Inheritance and Human Heredity Chapter 11 11.1 Basic Patterns of Human Inheritance Galactosemia • Recessive genetic disorder characterized by the inability of the body to digest galactose (a double sugar).

  8. Complex Inheritance and Human Heredity Chapter 11 11.1 Basic Patterns of Human Inheritance Dominant Genetic Disorders • Huntington’s disease affects the nervous system. • Achondroplasiais a genetic condition that causes small body size and limbs that are comparatively short. http://www.google.com/imgres?imgurl=http://www.sciencemuseum.org.uk/on-line/genes/images/1-3-5-1-4-2-1-1-1-0-0.jpg&imgrefurl=http://www.sciencemuseum.org.uk/on-line/genes/196.asp&usg=__JkYtf9tpKcdkcuO90BumlcVsiwc=&h=360&w=235&sz=27&hl=en&start=8&tbnid=7eiM3dG8p0oWwM:&tbnh=121&tbnw=79&prev=/images%3Fq%3DAchondroplasia%26hl%3Den

  9. Complex Inheritance and Human Heredity Chapter 11 11.1 Basic Patterns of Human Inheritance

  10. Complex Inheritance and Human Heredity Chapter 11

  11. Complex Inheritance and Human Heredity Chapter 11 11.1 Basic Patterns of Human Inheritance Pedigrees • A diagram that traces the inheritance of a particular trait through several generations

  12. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance Incomplete Dominance • The heterozygous phenotype is an intermediate phenotype between the two homozygous phenotypes.

  13. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance Codominance • Both alleles are expressed in the heterozygous condition. • Blood type demo and worksheet

  14. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance Multiple Alleles • ABO blood groups have three forms of alleles. IA IB i • Rh blood groups - Rh factor contains the Rh antigen and can cause problems when given Rh- people were given Rh+ blood. This trait is also controlled by multiple alleles (8). • Transfusion activity! - Who will survive?

  15. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance N=normal S=sickle Sickle-cell Disease –Codominant N=normal S=sickle Normal red blood cell • Changes in hemoglobin cause red blood cells to change to a sickle shape. • People who are heterozygous (NS) for the trait have both normal and sickle-shaped cells Sickle cell 7766x

  16. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance Coat Color of Rabbits • Multiple alleles can demonstrate a hierarchy of dominance. • In rabbits, four alleles code for coat color: C, cch, ch,and c.

  17. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance Coat Color of Rabbits Chinchilla Albino Light gray Dark gray Himalayan

  18. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance Epistasis • Variety is the result of one allele hiding the effects of another allele. eebb eeB_ E_bb E_B_ Dark pigment present in fur No dark pigment present in fur

  19. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance Sex Determination • Sex chromosomes determine an individual’s gender. • Males XY • Females XX

  20. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance • The X chromosome carries a variety of genes that are necessary for the development of both females and males. • The Y chromosome mainly has genes that relate to the development of male characteristics. (Testes Determining Factor) • Chromosome inactivation –one X in every female cell is turned off • Barr bodies –turned off X chromosome FYI calico cats-only females Sex- influenced traits - Baldness occurs more often in males than in females. It could be due to the differences in male and female hormones.

  21. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance Sex-Linked Traits • Genes located on the X chromosome (recessive) • Red-green color blindness -limited color vision; mostly in males Color blind test • Hemophilia– no AHF (anti-hemophilic factor) Also called bleeders disease. Muscular Dystrophy- incorrect protein (dystrophin) Mutant gene causes the wasting away of skeletal muscles. Many types of MD. Duchenne’s is usually fatal by age 20 due to cardiac failure. 1 in 4,000 males effected Sex-Linked Traits

  22. Colorblindness Father (normal vision) Normal vision Colorblind Male Female Daughter (normal vision) Son (normal vision) Mother (carrier) Daughter (carrier) Son (colorblind)

  23. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance Polygenic Traits • Polygenic traits arise from the interaction of multiple pairs of genes.

  24. Complex Inheritance and Human Heredity Chapter 11 Environmental Influences on genes • Environmental factors • Diet and exercise • Sunlight and water • Temperature • Karyotype—pictures of the pairs of homologous chromosomes are arranged in decreasing size. Used to identify chromosome disorders.

  25. Complex Inheritance and Human Heredity Chapter 11 11.3 Chromosomes and Human Heredity Nondisjunction disorders • Cell division during which sister chromatids fail to separate properly • Down syndrome-Chromosome disorder where individuals have an extra 21st chromosome. Also called trisomy 21. 1out of 800 babies are born with this. Caused by non-disjunction during meiosis. Visualizing Nondisjunction

  26. Disjunction disorders - Sex chromosomes do not separate properly during meiosis. 1.Turner syndrome - XO genotype. Female is sterile.2.Klinefelter syndrome - XXY genotype. Males are sterile with immature sex organs and some female characteristics.3. Metafemale - XXX genotype . Females tend to have learning disabilities and may enter menopause early or have cycle irregularities. Most have no affects from this.What union of gametes would have produced the above disorders?4. XYY - Normal male, but may be taller than average. Controversy about these males being antisocial and aggressive and a link to some crimes.

  27. Complex Inheritance and Human Heredity Chapter 11

  28. Complex Inheritance and Human Heredity Chapter 11 11.2 Complex Patterns of Inheritance Twin Studies • Helps scientists separate genetic contributions from environmental contributions • Traits that appear frequently in identical twins are at least partially controlled by heredity. • Traits expressed differently in identical twins are strongly influenced by environment.

  29. Complex Inheritance and Human Heredity Chapter 11 Chapter Resource Menu Chapter Diagnostic Questions Formative Test Questions Chapter Assessment Questions Standardized Test Practice biologygmh.com Glencoe Biology Transparencies Image Bank Vocabulary Animation Click on a hyperlink to view the corresponding lesson.

  30. Complex Inheritance and Human Heredity Chapter 11 Chapter Diagnostic Questions Identify the disease characterized by the absence of melanin. albinism cystic fibrosis galactosemia Tay-Sachs

  31. Complex Inheritance and Human Heredity Chapter 11 Chapter Diagnostic Questions An individual with Tay-Sachs disease would be identified by which symptom? excessive mucus production an enlarged liver a cherry-red spot on the back of the eye vision problems

  32. Complex Inheritance and Human Heredity A recessive allele is passed on by both parents. Chapter 11 Chapter Diagnostic Questions Under what circumstances will a recessive trait be expressed? One parent passes on the recessive allele. The individual is heterozygous for the trait. There is a mutation in the dominant gene.

  33. Complex Inheritance and Human Heredity It continues throughout a patient’s life, It is caused by acid excretion and results affecting bones and joints. in black urine. Chapter 11 11.1 Formative Questions Which of Dr. Garrod’s observations about alkaptonuria was most critical to his determination that it is a genetic disorder? It appears at birth and runs in families. It is linked to an enzyme deficiency.

  34. Complex Inheritance and Human Heredity Chapter 11 11.1 Formative Questions Which is the genotype of a person who is a carrier for a recessive genetic disorder? DD Dd dd dE

  35. Complex Inheritance and Human Heredity Chapter 11 11.1 Formative Questions Albinism is a recessive condition. If an albino squirrel is born to parents that both have normal fur color, what can you conclude about the genotype of the parents? at least one parent is a carrier both parents are carriers both parents are homozygous recessive at least one parent is homozygous dominant

  36. Complex Inheritance and Human Heredity Chapter 11 11.2 Formative Questions When a homozygous male animal with black fur is crossed with a homozygous female with white fur, they have offspring with gray fur. What type of inheritance does this represent? dosage compensation incomplete dominance multiple alleles sex-linked

  37. Complex Inheritance and Human Heredity Chapter 11 11.2 Formative Questions Of the 23 pairs of chromosomes in human cells, one pair is the _______. autosomes Barr bodies monosomes sex chromosomes

  38. Complex Inheritance and Human Heredity Chapter 11 11.2 Formative Questions Which is an example of a polygenic trait? blood type color blindness hemophilia skin color

  39. Complex Inheritance and Human Heredity Chapter 11 11.3 Formative Questions What does a karyotype show? The blood type of an individual. The locations of genes on a chromosome. The cell’s chromosomes arranged in order. The phenotype of individuals in a pedigree.

  40. Complex Inheritance and Human Heredity Chapter 11 11.3 Formative Questions What is occurring in this diagram? multiple alleles nondisjunction nonsynapsis trisomy

  41. Complex Inheritance and Human Heredity Chapter 11 11.3 Formative Questions What condition occurs when a person’s cells have an extra copy of chromosome 21? Down syndrome Klinefelter’s syndrome Tay-Sachs syndrome Turner’s syndrome

  42. Complex Inheritance and Human Heredity Chapter 11 Chapter Assessment Questions Use the figure to describe what the top horizontal line between numbers 1 and 2 indicates. 1 and 2 are siblings 1 and 2 are parents 1 and 2 are offspring 1 and 2 are carriers

  43. Complex Inheritance and Human Heredity Chapter 11 Chapter Assessment Questions Which is not an allele in the ABO blood group? IA IO IB i

  44. Complex Inheritance and Human Heredity Chapter 11 Chapter Assessment Questions Down Syndrome results from what change in chromosomes? one less chromosome on pair 12 one extra chromosome on pair 21 one less chromosome on pair 21 one extra chromosome on pair 12

  45. Complex Inheritance and Human Heredity Chapter 11 Standardized Test Practice If a genetic disorder is caused by a dominant allele, what is the genotype of those who do not have the disorder? heterozygous homozygous dominant homozygous recessive

  46. Complex Inheritance and Human Heredity Chapter 11 Standardized Test Practice Analyze this pedigree showing the inheritance of a dominant genetic disorder. Which would be the genotype of the first generation father? RR Rr rr

  47. Complex Inheritance and Human Heredity Chapter 11 Standardized Test Practice Shorthorn cattle have an allele for both red and white hair. When a red-haired cow is crossed with a white-haired bull, their calf has both red and white hairs scattered over its body. What type of inheritance does this represent? codominance dosage compensation epistasis sex-linked

More Related