What can chromosomes tell us? Male or female? What is the problem with this set of chromosomes? Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

What can chromosomes tell us? Objectives Define key terminology related to chromosomes. Explore the use of karyotyping. Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

Chromosomes are composed of DNA coiled around proteins (histones)

What can chromosomes tell us? Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

What can chromosomes tell us? Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. One chromosome of each homologous pair comes from the mother (called a maternal chromosome) and one comes from the father (paternal chromosome).  Homologous chromosomes are similar but not identical. Each carries the same genes in the same order, but the alleles for each trait may not be the same. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

What can chromosomes tell us? An autosome is a chromosome that is not an allosome (i.e., not a sex chromosome). Autosomes appear in pairs whose members have the same form but differ from other pairs in a diploid cell, whereas members of an allosome pair may differ from one another and thereby determine sex. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

What can chromosomes tell us? Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

What can chromosomes tell us? Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

What can chromosomes tell us? Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

What can chromosomes tell us? Questions State the difference between a diploid and haploid cell. What is an autosome? What are homologous chromosomes? If a diploid cell of an organism contains 38 chromosomes how many will a gamete contain? Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

What can chromosomes tell us? Karotype and karyogram Karyotype: A property of the cell – the number and type of chromosomes present. Karyogram: the image of this. Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

Non-disjunction Non-disjunction is one of the Two major occurrences of Meiosis (The other is Crossing Over) Non-disjunction is the failure of homologous chromosomes, or sister chromatids, to separate during meiosis. Non-disjunction results with the production of zygotes with abnormal chromosome numbers…… remember…. An abnormal chromosome number (abnormal amount of DNA) is damaging to the offspring.

Non-disjunctions usually occur in one of two fashions. What can chromosomes tell us? Non-disjunctions usually occur in one of two fashions. Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. The first is called Monosomy, the second is called Trisomy. If an organism has Trisomy 18 it has three chromosomes in the 18th set, Trisomy 21…. Three chromosomes in the 21st set. If an organism has Monosomy 23 it has only one chromosome in the 23rd set. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

What can chromosomes tell us? Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

Common Non-disjunction Disorders What can chromosomes tell us? Common Non-disjunction Disorders Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. Down’s Syndrome – Trisomy 21 Turner’s Syndrome – Monosomy 23 (X) Kleinfelter’s Syndrome – Trisomy 23 (XXY) Edward’s Syndrome – Trisomy 18 Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes

What can chromosomes tell us? Task Carry out the karyotyping activity on: http://www.biology.arizona.edu/human_bio/activities/karyotyping/karyotyping.html Link is on Haiku Outcomes 3: Describe karyotyping. 5: Successfully complete the activity on karyotyping. 7: Evaluate the uses and limitations of karyotyping. Key terms: karyotyping, chromosome, diploid, haploid, homologous, autosomes