Chromosomes and Human Inheritance Chapter 12. Impacts, Issues: Strange Genes, Tortured Minds  Exceptional creativity often accompanies neurobiological.

Slides:



Advertisements
Similar presentations
Inheritance Principles and Human Genetics
Advertisements

Patterns of Chromosome Inheritance
GENETICS! I LOVE PEAS MAN! GREGOR MENDEL.
Cell division When one cell divides into 2 identical clones.
Genes, Chromosomes, and Human Genetics Chapter 13.
Chapter 11 Mendel & The Gene Idea.
THE CHROMOSOMAL BASIS OF INHERITANCE
Chromosomes and Inheritance
Chromosomes and Human Inheritance
Genetics Chapter 29. Essential Must Know Terminology Chromosome: structure of DNA seen in cell division – Homologous chromosomes Autosomes: 22 homologs.
Human Genetics EQ: How can genetic patterns be analyzed to determine dominant or recessive inheritance patterns?
Chapter 12- Human Genetics
Human Genetics Chapter 14 in the Textbook.
Chapter 24: Patterns of Chromosome Inheritance
Chromosomes and Human Inheritance  Diploid = 46, Haploid = 23  Sex chromosomes different than others  Not homologous pairs  Female = two X chromosomes.
Changes in Chromosome Number
1. Somatic cells in humans have __________ chromosomes. A. 23 B. 46 C
Chromosomes and Human Inheritance
Inheritance & Human Genetic Patterns
Chapter 14: The Human Genome
Chromosomes and Human Genetics. The Chromosomal Basis of Inheritance A time to review A gene – a unit of information about a heritable trait – found at.
Heredity Study Guide Answer Key.
Chromosomes & Human Heredity
Chapter 7: Congenital and Genetic Disorders Pathophysiology Ms. Harris.
Inheritance Patterns and Human Genetics. Sex Chromosomes and Autosomes Sex Chromosomes contain genes that determine the gender of an individual. Many.
Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings PowerPoint ® Lecture Presentations for Biology Eighth Edition Neil Campbell.
Chromosomal Basis of Inheritance Chapter 15. Most genetics work done on fruit flies (little time to observe many generations) Thomas Morgan - fruit fly.
Non-Disjunction, Aneuploidy & Abnormalities in Chromosome Structure
Karyotype and Chromosomal Mutation Notes
Human Genetics Review – What is a GENE? A gene is the unit that controls traits Genes are passed from parents to offspring Genes are located on our chromosomes.
Ch. 15: Chromosomal Abnormalities
AP Biology Errors of Meiosis Chromosomal Abnormalities.
Tracing the Inheritance of the Human Y Chromosome
Chromosomal Basis of Inheritance Chapter 15. Genetic work done on fruit flies - takes little time to observe many generations. Thomas Morgan - fruit fly.
1 Chapter 11 Complex Inheritance and Human Heredity 11.3 Chromosomes and Human Heredity.
Errors of Meiosis Chromosomal Abnormalities Chromosomal abnormalities Incorrect number of chromosomes – nondisjunction chromosomes don’t separate properly.
Chapter 15 The Chromosomal Basis of Inheritance. Concept 15.2: Sex-linked genes exhibit unique patterns of inheritance In humans and some other animals,
Human Inheritance Chapter 14 sec. 1 and 2. Pedigree Analysis Pedigree = a family record that shows how a trait is inherited over several generations.
© 2006 W.W. Norton & Company, Inc. DISCOVER BIOLOGY 3/e 1 Chromosomes and Human Genetics Mendel was unaware of chromosomes  The physical structure of.
Human Genetics and the Pedigree. Section Objectives Understand how different mutations occur. Be able to identify different diseases and disorders.
 Studying humans requires alternative methods.  Human geneticists use.  Human are – Deduce the genotypes and phenotypes of individuals in.
Genes, Chromosomes, and Human Genetics
MEIOSIS AND CROSSING OVER Chromosomes are matched in homologous pairs Homologous chromosomes: the 2 members of a pair of chromosomes—contain genes for.
Sex-linked trait traits carried by genes located on the X or Y sex chromosomes genetically normal females:XX genetically normal males:XY Glossary.
Karyotypes and Pedigrees
Chromosomes and Human Genetics Chapter 11. Karyotyping Separating chromosomes for an individual The human chromosomes have been karyotyped to see what.
Human Inheritance Chapter 14 Biology Concepts and Applications, Eight Edition, by Starr, Evers, Starr. Brooks/Cole, Cengage Learning 2011.
Human Genetics. How many pairs of chromosomes are in each of our body cells? A.32 B.23 C.46 D pairs! This is 46 total; we get 23 from mom & 23 from.
Chromosomes and Human Genetics
Chromosomes and Human Inheritance
Chapter 15: The chromosomal basis of inheritance Chromosome Theory of inheritance Chromosome Theory of inheritance Genes have specific loci on chromosomes.
What was your favorite thing about winter break? What is a karyotype? What is the purpose of a karyotype?
Pick up warm-up from front table. Complete warm-up first! Complete warm-up first! When finished…get out sponge bob worksheet. Do you have any questions???
A __________ is a picture of an organism’s chromosomes
Errors in Meiosis Karyotypes & Chromosomal AbnormalitiesKaryotypes & Chromosomal Abnormalities.
Human Genetics. Karyotype Preparation – Stopping the Cycle Cultured cells are arrested at metaphase by adding colchicine This is when cells are most condensed.
Human Genetics Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Lecture Outline.
Genetic Variation. The Law of Segregation Mendel’s 1 st Law The 2 alleles of each gene pair separate into different gametes (egg or sperm) during meiosis.
Patterns of Inheritance Chapter 9 Part Complex Variations in Traits  A trait that is influenced by the products of multiple genes often occurs.
Chapter 12 Chromosomes and Human Inheritance. Impacts, Issues Video Strange Genes, Richly Tortured Minds.
Karyotypes Different organisms have different numbers of chromosomes Autosomes: Any chromosome that is not a sex chromosome (X or Y chromosome) – Humans.
THE CHROMOSOMAL BASIS OF INHERITANCE
Concept 15.3: Sex-linked genes exhibit unique patterns of inheritance
Chapter 15 The Chromosomal Basis of Inheritance
Chromosome Mutations.
PowerLecture: Chapter 12
What are they?? How do we use them?
Warm Up Complete Edpuzzle on pedigrees
What are they?? How do we use them?
Presentation transcript:

Chromosomes and Human Inheritance Chapter 12

Impacts, Issues: Strange Genes, Tortured Minds  Exceptional creativity often accompanies neurobiological disorders such as schizophrenia, autism, chronic depression, and bipolar disorder Examples: Lincoln, Woolf, and Picasso

12.1 Human Chromosomes  In humans, two sex chromosomes are the basis of sex – human males have XY sex chromosomes, females have XX  All other human chromosomes are autosomes

Sex Determination in Humans  Sex of a child is determined by the father Eggs have an X chromosome; sperm have X or Y

Sex Determination in Humans  The SRY gene on the Y chromosome is the master gene for male sex determination Triggers formation of testes, which produce the male sex hormone (testosterone)

Karyotyping  Karyotype A micrograph of all metaphase chromosomes in a cell, arranged in pairs by size, shape, and length Detects abnormal chromosome numbers

12.2 Autosomal Inheritance Patterns  Many human traits can be traced to autosomal dominant or recessive alleles that are inherited  Some of those alleles cause genetic disorders

Autosomal Dominant Inheritance  A dominant allele is expressed in homozygotes and heterozygotes With one homozygous recessive and one heterozygous parent, children have a 50% chance of inheriting and displaying the trait

Autosomal Recessive Inheritance  Autosomal recessive alleles are expressed only in homozygotes; heterozygotes are carriers and do not have the trait A child of two carriers has a 25% chance of expressing the trait

Fig. 12-4a, p. 188

Animation: Autosomal dominant inheritance

Animation: Autosomal recessive inheritance

12.3 Too Young to be Old  Progeria Genetic disorder that results in accelerated aging

12.4 Examples of X-Linked Inheritance  Mutated alleles on the X chromosome cause or contribute to over 300 genetic disorders

X-Linked Inheritance Patterns  More males than females have X-linked recessive genetic disorders Males have only one X chromosome and can express a single recessive allele

X-Linked Recessive Inheritance Patterns

Animation: X-linked inheritance

Some X-Linked Recessive Disorders  Hemophilia A Bleeding caused by lack of blood-clotting protein  Duchenne muscular dystrophy Degeneration of muscles caused by lack of the structural protein dystrophin

12.5 Heritable Changes in Chromosome Structure  On rare occasions, a chromosome’s structure changes; such changes are usually harmful or lethal, rarely neutral or beneficial  A segment of a chromosome may be duplicated, deleted, inverted, or translocated

Duplication  DNA sequences are repeated two or more times; may be caused by unequal crossovers in prophase I

Deletion  Loss of some portion of a chromosome; usually causes serious or lethal disorders Example: Cri-du-chat

Inversion  Part of the sequence of DNA becomes oriented in the reverse direction, with no molecular loss

Translocation  Typically, two broken chromosomes exchange parts (reciprocal translocation)

Nondisjunction  Changes in chromosome number can be caused by nondisjunction, when a pair of chromosomes fails to separate properly during mitosis or meiosis  Affects the chromosome number at fertilization Monosomy (n-1) Trisomy (n+1)

Nondisjunction

Autosomal Change and Down Syndrome  Only trisomy 21 (Down syndrome) allows survival to adulthood Characteristics include physical appearance, mental impairment, and heart defects  Incidence of nondisjunction increases with maternal age

Change in Sex Chromosome Number  Changes in sex chromosome number may impair learning or motor skills, or be undetected  Female sex chromosome abnormalities Turner syndrome (XO) XXX syndrome (three or more X chromosomes)  Male sex chromosome abnormalities Klinefelter syndrome (XXY) XYY syndrome

Turner Syndrome  XO (one unpaired X chromosome) Usually caused by nondisjunction in the father Results in females with undeveloped ovaries

Defining Genetic Disorders and Abnormalities  Genetic disorder An inherited condition that causes mild to severe medical problems, characterized by a specific set of symptoms (a syndrome)

12.8 Prospects in Human Genetics  Genetic analysis can provide parents with information about their future children  Genetic counseling Starts with parental genotypes, and genetic testing for known disorders Information is used to predict the probability of having a child with a genetic disorder

Prenatal Diagnosis  Tests done on an embryo or fetus before birth to screen for sex or genetic problems  Three types of prenatal diagnosis Amniocentesis Chorionic villus sampling (CVS)

After Preimplantation Diagnosis  When a severe problem is diagnosed, some parents choose an induced abortion  In some cases; surgery, prescription drugs, hormone replacement therapy, or dietary controls can minimize or eliminate symptoms of a genetic disorder