1. The Human Genome Karyotype: When chromosomes are photographed, then paired to observe size and number. Human Body Cell: Has 46 chromosomes, 2 of the 46 chromosomes are sex chromosomes and the remaining 44 are autosomal chromosomes 23rd pair of a Female is XX 23 rd pair of a Male is XY

2. Normal Human Karyotype

3. Normal Karyotype

4. Nondisjunction Failure of homologous pairs of chromosomes to separate properly during meiosis. This results in cells with an uneven number of chromosomes

6. Down Syndrome Down syndrome is caused by a person having three copies of chromosome 21 instead of two copies.

7. Down Syndrome Patient has 47 chromosomes Some characteristics are: short, broad hands; short height; broad head; round face; large tongue; slanting eyes and mental retardation

8. Down syndrome

9. Patau Syndrome Caused by an extra copy of chromosome 13. Severe mental deficiency, polydactylism, cleft lip/palate, heart problems low survival rate after 3 months.

10. Patau Syndrome Facial Clefting shown to the right

11. Patau Syndrome

12. Klinefelter’s syndrome Patient has 47 or 47+ chromosomes. (One to several extra X or Y) Male Characteristics: small testes, female-like breasts, female-like voice and retardation

13. Klinefelter’s Syndrome

14. Extra Y Chromosome Patient has 47 chromosomes (one extra Y chromosome. male 1 in 1000 males have 47-XYY Slightly taller, but rather normal development

15. Turner’s Syndrome Patient has 45 chromosomes Missing one X. Female, sterile dwarfism