1. DNA and RNA

3. DNA stands for Deoxyribonucleic Acid
In 1953, James Watson and Francis Crick developed the model called the Double Helix used to represent DNA.
But what about Rosalind Franklin?

4. Rosalind Franklin
Photograph 51 is the nickname given to an X-ray diffraction image of DNA taken by Raymond Gosling in May 1952, working as a PhD student under the supervision of Rosalind Franklin, at King's College London in Sir John Randall's group. It was critical evidence in identifying the structure of DNA.

6. What is inside of the Nucleus?
Chromosomes are threadlike structures that contain genetic information that is passed on from one generation of cells to the next.
Chromosomes are made up of DNA
Chromosomes are only visible during cell division. Otherwise genetic information is known as chromatin.

7. Chromatin

8. Parts of the chromosome
Centromere - the part of a chromosome that links sister chromatids
Chromatid - one copy of a duplicated chromosome, which is generally joined to the other copy by a single centromere.
Gene segment – segment of DNA that codes for a trait

9. Chromosomes

10. Where is Your DNA?
DNA is coiled up to make chromosomes found in the nucleus.
A segment of DNA is a gene that codes for a certain trait. (skin tone, eye color)

12. Regents Practice Question # 1
Which model best represents the relationship between a cell, a nucleus, a gene, and a chromosome?

13. Regents Practice Question # 1 (Answer)
Which model best represents the relationship between a cell, a nucleus, a gene, and a chromosome?
Correct Answer

14. Regents Practice Question # 2
Which diagram represents the relative sizes of the structures listed below?

15. Regents Practice Question # 2 (Answer)
Which diagram represents the relative sizes of the structures listed below?
Correct
Answer

16. DNA
DNA is called the blueprint of life because it contains the instructions for building an organism and ensuring that organism functions correctly.

17. Structure of DNA
DNA belongs to the class of biochemical molecules known as nucleic acids
This Twisted Ladder is made of nucleotides
The sides of the ladder are composed (made) of alternating deoxyribose sugars and phosphates.
The rungs of the ladder are composed of nitrogenous bases.

18. A Nucleotide is the building block of nucleic acids
A Nucleotide is the building block of nucleic acids. An organic compound made of one phosphate, nitrogenous base, and a sugar.

20. Nitrogenous Base Pair Adenine pairs to Thymine
Guanine pairs to Cytosine

21. Your Turn
A T T C G C G A A T T G
T A A G C G C T T A A C
T G G A T C C G T G A A
A C C T A G G C A C T T

22. DNA is Important
It carries genetic information from one generation to the next
DNA sequences create genes which then determine inherited traits
DNA can be easily copied during the creation of new cells

23. DNA REPLICATION
Replication is the process where DNA makes a copy of itself. WHY?
During cell division the genetic information needs to be passed to the daughter cells

24. DNA Replication Process
DNA separates into 2 strands unzipping itself with an enzyme called Helicase
One half of the old strand is always kept as a template for the new strand. DNA polymerase is an enzyme that matches nucleotides to old strand.
2 daughter strands each consisting of an old DNA and a new DNA strand

25. DNA Replication in Use

26. DNA Fingerprinting or Gel Electrophoresis A process used to compare DNA samples from different sources.

27. DNA Fingerprinting (Gel Electrophoresis)
Steps of DNA fingerprinting
DNA is cut using restriction enzymes, then fragments are placed in gel well
Electricity is applied to gel
DNA molecules move from negative to positive charged ends of gel
Smaller DNA segments move faster and farther than larger DNA segments

29. Uses of DNA Fingerprinting
Solve crimes
Determine Paternity
Establish Evolutionary Relationships

32. Proteins Synthesis
Genes control the production of proteins which occurs in the ribosomes.
Proteins are in every cell, tissue, muscle and bone – two million proteins in your body.
DNA can’t leave the nucleus but it needs to send instructions to the ribosomes so proteins can be made.
DNA sends a messenger out to the ribosome that carries the instructions for making the proteins.

33. What is RNA?
Ribonucleic Acid - RNA is the messenger that carries the instructions to the ribosomes so proteins can be made.
Three Types of RNA
mRNA-messenger
tRNA-transfer
rRNA-ribosomal

34. Structure of RNA Single stranded
It has uracil for a nitrogenous base instead of thymine
Complimentary base pairs are:
Cytosine-Guanine
Adenine-Uracil

36. Making A Protein starts with Transcription
Transcription is the process where a DNA molecule makes the messenger RNA molecule in the nucleus so genetic instructions can leave the nucleus.
Done by copying part of the base sequence of the DNA into a strand of RNA
RNA polyermase unzips the DNA strand.

39. Translation happens when mRNA arrives at the ribosome
Translation allows the cell to use information from mRNA to produce proteins that are built from amino acids
DNA mRNA Protein
Transcription Translation

42. Genetic Code
A codon consists of 3 nitrogenous bases that code for a single amino acid that is to be added to the growing protein chain.
Codons are located on the mRNA
There are just 22 different amino acids that exist.

45. MUTATIONS
Mutations are changes in the DNA sequence that affect genetic information.
Mutations provide genetic variations in a species
Not all mutations are harmful, some give an advantage to a species

46. Three Types of Mutations
Mutations can affect anywhere from a single DNA building block (base pair) to a large segment of a chromosome that includes multiple genes.
Substitution
Deletion
Insertion

47. Substitution
Occurs when one nitrogenous base is substituted in place of another one

48. Insertion
Occurs when one extra nitrogenous base is added into the DNA sequence

49. Deletion
Occur when one nitrogenous base is missing from the sequence

50. Causes of Mutations Two ways DNA can be mutated:
Mutations can be inherited
Mutations can be acquired
Environmental damage
Mistakes when DNA is copied

51. Karyotype
A photograph of an organism’s chromosomes
Typical Karyotype

52. Mutagens from our Environment
Mutagens are environmental factors that cause mutations. They include but are not limited to:
High Temperature
Toxic chemicals (pesticides)
Radiation (nuclear and solar)

53. Nature vs Genetic Engineering

55. Selective Breeding
There are different ways of moving genes to produce desirable traits. For both plants and animals, one of the more traditional ways is through selective breeding.
Selective breeding is a method of improving species by allowing only those organisms with desirable traits to produce the next generation.

56. Examples of Selective Breeding

57. Uses of selective breeding

58. Genetically Modified Organisms (GMOs)

59. What are GMO’s
any organism whose genetic material has been altered using genetic engineering techniques.
Also called transgenic organism – transfer of genes

62. Real or Photoshop?

63. Real or photoshop

64. Real or photoshop?

65. Real or Photoshop?

66. Example of GMO technique

67. Remember: Recombinant DNA using a bacteria cell (Gene Cloning)

70. Cloning
Cloning is the process that produces exact copies of a single cell or organism

71. Types of Cloning
Gene cloning- produces copies of genes or segments of DNA (Recombinant DNA)
Reproductive cloning - produces copies of whole animals
Therapeutic cloning - produces embryonic stem cells for experiments aimed at creating tissues to replace injured or diseased tissues.

72. Reproductive Cloning

73. Steps for Reproductive Cloning
A body cell is taken from a donor animal A
An egg cell is taken from a donor animal B
The nucleus is removed from the egg.
The body cell and egg are fused by electricity
The fused cell begins dividing-embryo
Embryo implanted into the uterus of foster mother.
The embryo develops into cloned animal of A.

75. Therapeutic cloning
Therapeutic cloning involves creating a cloned embryo for the sole purpose of producing embryonic stem cells with the same DNA as the donor cell.
These stem cells can be used in experiments aimed at understanding disease and developing new treatments for disease
The richest source of embryonic stem cells is tissue formed during the first five days after the egg has started to divide.