Chromosomes and Karyotypes Chromosomes are comprised of a single, uninterrupted DNA molecule and proteins (histones) A karyotype is a visual display of.

Slides:

Advertisements

Similar presentations

February 23, 2009 Objective: Discuss the effects of nondisjunction

Advertisements

When Meiosis goes wrong…

Chapter 9 Meiosis.

Achondroplasia.

CHAPTER 8B REVIEW.

Chromosomes & Human Heredity

Chromosomes. Chromosome Tightly coiled DNA form Found during mitosis and meiosis Made mostly of DNA and proteins Centromere- point of attachment Chromatids-

11.3 CHROMOSOMES & HUMAN HEREDITY

Chromosomes. Learning Objectives By the end of this class you should understand: The purpose of a karyotype The reason mitosis must be stimulated during.

Contributing to Future Generations. Where Do My Chromosomes Come From?  Every somatic cell (body cell) has 2 sets of chromosomes  1 set from mom & 1.

Meiosis/ Karyotypes Unit 6.

AP Biology Errors of Meiosis Chromosomal Abnormalities.

11.3 CHROMOSOMES & HUMAN HEREDITY

Errors of Meiosis Chromosomal Abnormalities Chromosomal abnormalities Incorrect number of chromosomes – nondisjunction chromosomes don’t separate properly.

Chromosomes: normal and aberrant structure and karyotypes n Chromosomes are comprised of a single, uninterrupted DNA molecule complexed with proteins (histones.

Genetic Disorders A disease caused by a different form of a gene called a variation, or an alteration of a gene called a mutation.

1. CHROMOSOMES 2 CHROMOSOME NUMBER  All cells in the human body (SOMATIC CELLS) have 46 or 23 pairs of chromosomes  Called the DIPLOID or 2n number.

1copyright cmassengale. Chromosomes 2 Chromosome Number All cells in the human body (SOMATIC CELLS) have 46 or 23 pairs of chromosomes Called the DIPLOID.

KARYOTYPING Honors Biology. What and How? Used as a way to “see” the chromosomes Pairs up homologous chromosomes Allows for detection of several genetic.

1. Chromosomes 2 Chromosome Number All cells in the human body (SOMATIC CELLS) have 46 or 23 pairs of chromosomes Called the DIPLOID or 2n number GAMETES.

AP Biology Errors of Meiosis Chromosomal Abnormalities.

Meiosis Review Chapter 11.

Chromosomes and Karyotypes What is a Chromosome Terminology Chromosomal Mutations Differences among species Karyotypes Nondisjunction disorders.

Human Female Karyotype

Chromosomal Abnormalities. Nondisjunction Incorrect number of chromosomes  nondisjunction  chromosomes don’t separate properly during meiosis.

Karyotyping Biology Miss Schwipperty. Questions  How many chromosomes come from your Father?  How many chromosomes come from your Mother?  What are.

MEIOSIS (making sperm and eggs…) We ’ re NOT talking about making babies, we ’ re talking about making the CELLS that make babies – eggs and sperm! Eggs.

MEIOSIS AND CROSSING OVER Chromosomes are matched in homologous pairs Homologous chromosomes: the 2 members of a pair of chromosomes—contain genes for.

Chromosomes (Eukaryotic DNA Structure). When the cell is not dividing, DNA is long and stringy and called chromatin.

Karyotypes Objective: E6 - Describe how techniques such as chromosomal analysis (karyotypes) are used to study the genome of organisms.

Errors in Meiosis Karyotypes & Chromosomal AbnormalitiesKaryotypes & Chromosomal Abnormalities.

By Mr. Simonds EQ: How are traits passed from parents to offspring?

MEIOSIS 3.3 & Meiosis: A reduction division of a diploid nucleus to form four haploid nuclei. This allows for a sexual life cycle in living organisms.

Meiosis, Karyotypes and Non-Disjunction. Meiosis is the process of cell division that forms gametes (sex cells) sperm and eggs. How many chromosomes do.

Mistakes in Meiosis. Non-Disjunction a type of mistake in meiosis that happens to the CHROMOSOME It is the failure of homologous chromosomes to separate.

What can chromosomes tell us?

Karyotype Notes. What each of the human chromosomes look like.

2B: creating sperm and egg 2D: fertilization creates new genetic combinations 2E: each parent contributes half of their DNA 2F: sex chromosomes determine.

11.3 Assessment Answers.

Karyotypes Different organisms have different numbers of chromosomes Autosomes: Any chromosome that is not a sex chromosome (X or Y chromosome) – Humans.

Chapter 11-3 Chromosomes & Human Heredity. Focus Questions: How are Karyotypes used to study genetic disorders? What is the role of Telomeres? How is.

Meiotic Cell Division and Sexual Reproduction

Meiosis Chapter 8.

Chromosomal Mutations

Karyotypes Objective: Learn and Identify characteristics of Karyotypes

CHROMOSOMES AND KARYOTYPING.

Standard 2 Cell Division Chromosomes Boggie.

Mutations Practice Quiz

Karyotype A photo of the chromosomes in a dividing cell that show the chromosomes arranged by size. Purpose of a Karyotype: (1) to detect abnormalities.

Chromosomal Mutations & Karyotypes

Nondisjunction GT pg (Section 13.10) chromosomal mutation, p.408 (Last paragraph)?? Reg- p. 401, top 374.

Meiosis & Chromosomes Chapter 10.1 and 11.3.

Standard 2 Cell Division “Chromosome Waltz”.

Karyotype Notes.

Meiosis Chapter 8.

Chromosomes & Karyotypes

Title of notes: Karyotypes

CHROMOSOMES As a eukaryotic cell prepares to divide the DNA

8.3 Human Genetics and Mutations

Analyze how environmental factors can influence a persons phenotype?

Karyotype A photo of the chromosomes in a dividing cell that show the chromosomes arranged by size. Purpose of a Karyotype: (1) to detect abnormalities.

Bell Work 2. Which cells are NOT formed during meiosis? Somatic cells

Karyotypes Pages in textbook.

Presentation transcript:

Chromosomes and Karyotypes Chromosomes are comprised of a single, uninterrupted DNA molecule and proteins (histones) A karyotype is a visual display of the chromosomes of an individual.

Karyotype A picture of a complete diploid set of chromosomes arranged in pairs of decreasing size

Amniocentesis Weeks

Chronic Villus Sampling (CVS) Weeks

How Do We Look at the Chromosomes? Cells are treated with Colchicine - WHY? Prevents Spindle Fibers form forming Cells will be stuck in Metaphase Chromosomes will be condensed and VISIBLE Cells are placed in pure water (hypotonic) – WHY?

Color or Black and White?

Black & White – Most Common Each chromosome has a characteristic banding pattern that helps to identify them; both chromosomes in a pair will have the same banding pattern.

Let’s Make It Pretty - Way to Go Photoshop Karyotypes are arranged with the short arm of the chromosome on top, and the long arm on the bottom, called p and q, respectively.

Sex Chromosomes- determine an individual’s sex »X and Y chromosome Autosomes-the other 44 chromosomes

Normal Female Karyotype

Normal Male Karyotype

Let’s Make It Pretty - Way to Go Photoshop So, whose Karyotype is this?

What is wrong with this picture?

Nondisjunction Occurs when homologous chromosomes or sister chromatids fail to separate during meiosis Results in gametes with an abnormal number of chromosomes (missing or extra)

Meiosis I Meiosis II Results in Trisomy Results in Monosomy

Nondisjunction

Does this remind you of something? Hint: What happened when we played – Mutated Tumor suppressor gene?

Nondisjunction Consequences Nondisjunction produces abnormal gametes (sperm and egg) Fertilization wit an abnormal gamete can result in Monosomy or Trisomy Monosomy – missing 1 chromosome Trisomy – having 1 extra Most monosomies and trisomies do not survive to birth

Down Syndrome Trisomy 21

1 in 700 babies (6000 babies/year) 400,000 Americans Rate increases with maternal age 5% of cases traced to father

Turner Syndrome (XO) 1 in 2500 females Monosomy of X chromosome 10% of all miscarriages Highly variable

Turner Syndrome (X0)

Kleinfelter’s Syndrome (XXY) 1 in males Many times they may not know