1. November 5, 2013 Signed interims should be placed in the IN BOX
Warm Up: In what two processes are you able to see DNA through a microscope because chromosomes form?
Homework: Clicker quiz tomorrow, work on Project. The project is due Friday!
Class Work: Mutations discussed via PPT.
Question of the day: What is a mutation?

2. Don’t let this happen to you!!

3. Deoxyribonucleic Acid
Double Stranded Molecule
First Modeled in 1953 by James Watson & Francis Crick
The genes of heredity are found in the DNA molecule.

4. Chromatins& Chromosomes
Chromatins A strand of DNA which condenses to form a chromosome during cell division.
A Chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.
Animation

5. DNA Sequences A goes with T C goes with G A adenosine T thymine
C cytosine
G guanine
Nucleotide means ½ of a base pairs

6. Codons Table: DNA 3 letter Words code to Amino Acids
A gene codes for a protein
Proteins are made of amino acids
Each Codon codes for an amino acid or a Stop signal.
For example: ATG is a codon coding for the amino acid Methionine

7. A gene genetic sequence broken down into codons.

8. MUTATIONS
Changes in DNA (the sequence of base pairs or a change in a chromosomes) that affect genetic information (perhaps changes in the protein coded for by the gene)

9. Mutations
Can be good, the organism is more successful in its environment and reproduces to pass on the beneficial gene
Can be bad, the organism or its offspring are less successful in its environment
Can be neutral, the organism is neither harmed or helped.

10. Gene Mutations (Using Analogy of the Sentence)
Point Mutations – changes in one or a few nucleotides (bases)
Substitution (analogy)
THE FAT CAT ATE THE RAT
THE FAT HAT ATE THE RAT
Insertion
THE FAT CAT XLW ATE THE RAT
Deletion XLW is Inserted
THE FAT ATE THE RAT
CAT is deleted

11. Gene Mutations
Frameshift Mutations – shifts the reading frame of the genetic message so that the protein may not be able to perform its function.
Insertion
THE FAT CAT ATE THE RAT
THE FAT HCA TAT ETH ERA T
Deletion
TEF ATC ATA TET GER AT H H

12. Chromosome Mutations
Changes in number and structure of entire chromosomes
Original Chromosome ABC * DEF
Deletion AC * DEF
Duplication ABBC * DEF
Inversion AED * CBF
Translocation ABC * JKL
GHI * DEF

13. Evidence of Chromosome Mutations in Humans
In 2005, scientific journal published show that it turns out that chromosome 2, which is unique to the humans emerged as a result of the head-to-head fusion of two ancestral chromosomes that remain separate in other primates. Three genetic indicators provide strong evidence of fusion. First, the banding (or dye pattern) of human chromosome 2 closely matches that of two separate chromosomes found in apes (chimp chromosome 2 and an extra chromosome that does not match any other human chromosome). Second, a chromosome normally has one centromere, or central point at which a chromosome's two identical strands are joined. Yet remnants of a second, presumably inactive centromere can be found on human chromosome 2. And third, whereas a normal chromosome has readily identifiable, repeating DNA sequences called telomeres at both ends, chromosome 2 also has telomere sequences not only at both ends but also in the middle.

14. Significance of Mutations
Most are neutral
Eye color
Birth marks
Some are harmful
Tay Sachs Disease
Down Syndrome
Some are beneficial
Immunity to HIV

15. What Causes Mutations?
There are two ways in which DNA can become mutated:
Mutations can be inherited.
Parent to child
Mutations can be acquired.
Environmental damage
Mistakes when DNA is copied
These can lead to cancer.

16. Chromosome Mutations Chromosome 21 does not separate correctly.
Down Syndrome
Chromosome 21 does not separate correctly.
They have 47 chromosomes in stead of 46.
Children with Down Syndrome develop slower, may have heart and stomach illnesses and vary greatly in their degree of intelligence.

17. Chromosome Mutations Cri-du-chat Syndrome
Deletion of material on 5th chromosome
Characterized by the cat-like cry made by cri-du-chat babies
Varied levels of metal handicaps

18. Sex Chromosome Abnormalities
Normal Sex Chromosomes Chromosomes XY (male gender)
XX (female gender)
Klinefelter’s Syndrome
XXY, XXYY, XXXY
Male
Sterility
Small testicles
Breast enlargement

19. Sex Chromosome Abnormalities
XYY Syndrome
Normal male traits
Often tall and thin
Associated with antisocial and behavioral problems

20. Sex Chromosome Mutations
Turner’s Syndrome X
Female
sex organs don't mature at adolescence
sterility
short stature

21. Sex Chromosome Mutations
Karyotype Diagram
XXX
Trisomy X
Female
Little or no visible differences
tall stature
learning disabilities
limited fertility