Bell Ringer Write the questions and answers Pedigree

Bell Ringer: Write the questions and answers Pedigree Questions: 1. A circle represents a ________ 2. A square represents a _______ 3. A ______ line connects a circle and square. 4. What are the roman numerals for? 5. Half shaded means an individual is a ______ 6. Fully shaded means an individual is ______

Bell Ringer: Half Sheet of Paper 1. List all the Blood Phenotypes and their Blood Genotypes. 2. Cross Heterozygous A with Homozygous B 3. Cross O with Heterozygous B 4. Cross AB with Homozygous A !Determine G. Possibilities and G. Ratios! !Determine P. Possibilities and P. Ratios!

Mutations and Nondisjunction Genetics: When things don’t go as planned!

Joke of the Day:

Joke of the Day:

Mutations and Nondisjunction Genetics: When things don’t go as planned!

"Mutation. It is the key to our evolution. It has enabled us to evolve from a single-celled organism into the dominant species on the planet. "

The Human Genome: Facts Genome: Complete set of DNA/Genetic Material In every Cell: 46 Chromosomes or 23 Homologous pairs. Pairs #1 -22: Autosomes Pair #23: Sex Chromosomes – X and Y (Gender) Normal Male: 46 XY Normal Female: 46 XX • 3. 3 Billion Nucleotides • 30, 000 Genes (estimated)

Karyotype Photograph of a full set of chromosomes in ordered pairs. (microscope) Usually look at chromosomes in white blood cells Identify chromosomal alterations that may result in a genetic disorder.

Karyotype Normal Female Normal Male

Mutations Mutation: Changes in the DNA sequence that affect genetic code. The ultimate source of genetic variability in a population. Most Mutations are neutral

Mutations and Inheritance If a mutation occurs during the formation of gametes, it may be passed to the offspring. If a mutation occurs later in life inside a body cell, the mutation is not inherited.

2 Types of Mutations

Gene Mutation: a change in a single gene Mutation Example: Point Mutation - One nucleotide (letter) in the DNA is changed. Disorder Example: Tay Sach’s Disease – Lipid accumulation in brain

Chromosome Mutations Chromosome Mutation: change in the whole chromosome. Mutation Example: Deletion, Duplication, Inversion, or Translocation Disorder Example: Fragile X – Severe learning disabilities

Chromosome Mutations

Nondisjunction During Meiosis, the homologous chromosomes fail to separate properly Causes an abnormal number of chromosomes in the gametes and may lead to disorders.

Nondisjunction Homologous chromosomes fail to separate Meiosis I: Nondisjunction Meiosis II

Down’s Syndrome Trisomy 21: Down’s Syndrome Occurs when there is an extra copy of chromosome 21. This causes problems with the way the body and brain develop. Causes mild to severe mental retardation. 1 in 800 babies in the US is born with Down’s Syndrome.

Karyotype for Down’s Syndrome

Sex Chromosome Disorders Turner’s Syndrome: A problem in females where she only inherits one X chromosome. . The woman is sterile. (45 XO Turner’s) Kleinfelter’s Syndrome: A problem in males where he inherits an extra X chromosome. The man is sterile. (47 XXY Kleinfelter’s).

Sex Chromosome Disorders Karyotypes Turner’s Syndrome 45 XO Kleinfelter’s Syndrome

Sex Chromosome Disorders Jacob’s Syndrome: Genetic condition in which a human male has an extra male (Y) chromosome, . (47, XYY) Occurs in 1, 000 male births. Increased average height Delayed puberty Learning difficulties Speech problems

Jacob’s Syndrome

Karyotype Activity