1. Genes and Gene Technology
Chapter 6
Genes and Gene Technology

2. DNA Deoxyribonucleic acid
Hereditary material that controls all the activities of a cell
contains the information to make new cells
provide instructions for making proteins

4. Nucleotide A subunit of DNA
Consists of a sugar, a phosphate, and one of the four nitrogenous bases
A, C, T or G
Nucleic acid- a biochemical that stores information needed to build proteins

6. A, T, C, G Adnenine – pairs with Thymine Thymine – pairs with Adenine
Cytosine – pairs with Guanine
Guanine – pairs with Cytosine

7. Ribosome
A small organelle in cells where proteins are made from amino acids

8. What Do Genes Look Like? Chromosomes are made of DNA and proteins
Traits (appearance)are determined by genes (codes of DNA)
Genes are passed from generation to generation
Genes are located on the chromosomes

9. The gene material must
Able to supply instructions for cell processes and for building cell structures
Able to be copied each time a cell divides

10. Early Studies
Suggested that DNA was a simple molecule and therefore thought protein carried heredity information
1940’s – scientists discover that genes of bacteria are made of DNA

11. Chargaff’s Rules
1950’s – Erwin Chargaff found the amount in adenine in DNA always matches the amount of thymine
Also, the amount of cytosine always matches the amount of guanine
Clue 1 to the structure of DNA

12. A Picture of DNA Clue 2 for the shape of DNA
Rosalind Franklin ( )
Used x-ray diffraction (bombard the DNA molecule with x-rays that bounce off and create a pattern)
Created a picture of DNA molecule

13. Franklin’s Picture Died at the age of 38 due to cancer
Discriminated throughout her career by Wilkins and Watson

15. Watson and Crick
Discovered that DNA was helical in shape (double helix)
Franklin’s picture
Spiral shape
Chargaff’s rules
Bases in pairs
Double strand

16. Watson and Crick Won the Nobel prize in 1962 with Maurice Wilkins
Rosalind Franklin receive no mention because the Nobel Prize is not awarded posthumously
After her death, W and C gave her credit to their success

17. Because adenine always bonds with thymine, and cytosine always bonds with guanine, one side of a DNA molecule is complementary to the other.

18. If the DNA segment is GATTACTTTAACCT
The complementary strand would be:
CTAATGAAATTGGA
The complementary base pairing allows DNA to REPLICATE or copy itself

19. DNA replicates by splitting down the middle where the nitrogen bases meet.
The bases on each side of the molecule are used as a template, or pattern for a new complementary side.
This creates two identical molecules of DNA.

20. DNA DNA functions the same way for all organisms
DNA makes us the same and makes us unique

21. The bases on one side of the DNA molecule can be put in any order, allowing an enormous variety of genes.
Each gene consists of a string of bases.
The order of the bases gives the cell information about how to make each trait.

22. The double helix wraps around a protein known as a histone and coils and condenses until it appears as a chromosome

23. The Importance of Environment
Remember, genes only influence your development
Other things affect your growth and development
Nutrition, exercise

24. Mutation?
Is this possible?

25. How about this?

26. Mutation A change in the order of the bases in an organism’s DNA
Deletion –removing a base
Insertion – adding a base
Substitution – Switching bases

27. Insertion
Substitution

28. Mutation – Leucistic

29. Mutagen
Anything that can damage or cause changes in DNA