1. Chromosomal Mutations
Changes in pieces of the chromosome
Deletion, Duplication, Inversion, Translocation

2. histone proteins forming bead-like units or “nucleosomes”
Chromosome Structure
DNA wrapped around
histone proteins forming bead-like units or “nucleosomes”
These are coiled forming a “super coil” which coils to form a “chromosome”

3. Chromosomal Analysis
Karyotype – Photograph of chromosomes of an individual arranged by size and shape

4. Chromosome Determine Sex of Individual
Autosomes – Chromosomes that are the same in male and female (chromosome pairs 1-22)
Sex chromosomes – One pair that determines sex (chromosome pair 23- X is longer)
XX – Female, XY - Male
Normal Female
Normal Male

7. CHROMOSOMAL
ABNORMALITIES

8. Problems with chromosome number result from defective gametes.
They occur because homologous chromosomes separated incorrectly during MEIOSIS (non-disjunction.)
This defective gamete becomes a part of the zygote and new organism.

9. Chromosomes Number Abnormalities
Trisomy – Diploid cell with an extra chromosome
Trisomy 13 (Patau Syndrome)
Trisomy 21 (Down’s Syndrome)

10. Monosomy – Diploid cell missing a chromosome
(Turner’s Syndrome – Short Stature,
sterility, other health complications are possible)

11. Turner’s Syndrome 1 in 5,000 births 45 chromosomes X only
#23 Monosomy Nondisjunction

12. Polyploidy – An extra entire set of chromosomes; plants with polyploidy tend to be heartier

13. Chromosome Structure Abnormalities
Mutations- Change in genetic material 4 Types:
1. Deletion – Fragment breaks off and is lost
2. Duplication –
Fragment breaks off and attaches to homologous chromosomes giving it two copies

14. 3. Inversion –
Fragment breaks off and reattaches backwards
4. Translocation–
Fragment breaks off and joins non-homologous chromosome

16. **They provide genetic variety in a species.
Many mutations don’t have an effect.
Some are harmful while others are helpful.
**They provide genetic variety in a species.

17. How can you tell the difference between a gene mutation and a chromosomal mutation?
Which is a gene mutation?
Which is a chromosomal mutation?