1. Karyotypes
Pages in textbook

2. What is a karyotype?
Picture of a full genome (full set of genetics information that an organism carries in its DNA)
Shows the complete diploid set of chromosomes grouped together in homologous pairs, arranged in order of decreasing size
Picture is taken during mitosis when chromosomes are fully condensed and easy to view
Review Question: What phase would this be?

3. Chromosomes
Review: How many total chromosomes are in an average human cell?

4. Looking at this karyotype, how are the chromosomes arranged?
Normal Karyotype
Looking at this karyotype, how are the chromosomes arranged?

5. What can karyotypes show?
Humans have 23 pairs of chromosomes (46 chromosomes total)
Pairs 1-22 are autosomes
The 23rd pair are the sex chromosomes that determine the gender of an individual
Chromosomal mutations
Insertion
Missing piece of a chromosome
Missing Chromosome

6. Sex Chromosomes Average female sex chromosomes are XX
Average male sex chromosomes are XY
Thinking Question: Which parent determines the gender of each child?
The X chromosome contains more than 1400 genes
The Y chromosome contains only about 158 genes; associated with male sex characteristics and sperm development mainly

7. Normal Karyotype

8. Nondisjunction
When one pair of sister chromatids fail to separate during Anaphase I or II of Meiosis
Results in a gamete with an extra chromosome or a gamete with one less chromosome
Insertion (Down’s Syndrome, Klinefelter Syndrome)
Deletion (Cri Du Chat)
Missing chromosomes (Turner Syndrome)

10. Great Video on Nondisjunction