1. Add to table of Contents: Karyotype ExamplePg. 58 KaryotypesPg. 59

2. Review: Humans have ___ pairs, ____ (total)chromosomes. The last pair is the sex chromosomes. XX = XY = 23 46 girl boy

3. X X Y X There will always be a 50% change that a baby will be a boy or 50% girl.

4. Karyotypes Pg. 59 Autosomes = Pairs 1  22 Sex chromosomes = Pair 23

5. Diploid – contains 2 of every type of chromosomes (1 from mom, 1 from dad) = 2n. Found in all somatic cells =body cells Ex. Skin, muscle, nerve

6. Haploid – contains only 1 of every type of chromosome. = 1n = reproductive cells Found in gametes = sperm and egg

7. Karyotype- A diagram that shows a cell’s chromosomes arranged in order from largest to smallest.

10. Down Syndrome

12. Down’s syndrome=Trisomy 21 = 3 #21 chromosomes.

13. Head and facial features often associated with Down Syndrome: Flattened back of head. Almond-shaped eyes, with eye lid a little droopy. Sometimes a whitish pupil. Slightly flattened bridge across nose. Smallish ears, slightly lower on the head, with a small fold on top. Slightly protruding tongue.

15. Risk of Down Syndrome

16. Turner’s Syndrome = only 1 X chromosome

17. Turner’s Syndrome Turner’s syndrome It is a chromosomal disorder affecting females in which all or part of one of the X chromosomes is absent.X chromosomes Occurring in 1 out of every 2500 girls There are characteristic physical abnormalities, such as short stature, broad chest, infertility, low hairline, low- set ears, and webbed neck. short staturelow- set earswebbed neck Concurrent health concerns are also frequently present, including congenital heart diseasecongenital heart disease

19. Klinefelter's syndrome = 2XX and 1Y

20. Klinefelter’s Syndrome Klinefelter's syndrome, 47,XXY or XXY syndrome is a condition caused by a chromosome aneuploidy. Affected individuals have at least two X chromosomes and at least one Y chromosome.[1] Klinefelter's syndrome is the most common sex chromosome disorderchromosomeaneuploidyX chromosomesY chromosome The principal effects are development of small testicles and infertility.testicles infertility The condition exists in roughly 1 out of every 1000 males Because of the extra chromosome, individuals with the condition are usually referred to as "XXY Males", or "47, XXY Males".extra chromosome

21. Construct a Karyotype

22. Cri-du-chat

23. The 23 rd pair of chromosomes that differ in males and females in humans are called the: A. Autosomes B. Sex chromosomes C. Multiple allleles D. Polygenes

24. X X Y X What percent chance will there be that a baby is a girl? A boy?

25. Mendel said that reproductive cells have 1 chromosome for every trait. This is supported by: A. Diploid cells are produced by mitosis B. Haploid cells are produced by mitosis C. Diploid cells are produced by meiosis D. Haploid cells are produced by meiosis