1. Genetics and Heredity

2. DNA D.N.A. - Deoxyribonucleic Acid Molecule made of: 1. Deoxy Sugar
2. Combination of four nitrogen bases
Either: a. Guanine
b. Cytosine
c. Thymine
d. Adenine
COOL FACT!: The sum total of combinations that these four bases are capable of creating are greater than all the stars visible in the night time sky!!

3. DNA Nitrogen bases pair up Pairing creates a ladder shape
Cytosine & Guanine
Thymine & Adenine
Pairing creates a ladder shape
Angle of bonds creates a twist
Ladder and Twist produces the famous
“Double Helix”

4. DNA DNA resides in all cells Each strand forms a chromosome
Nucleus
Cell
DNA resides in all cells
Inside the nucleus
Each strand forms a chromosome
DNA

5. DNA DNA is found in all living cells
It controls all functions inside a cell
It stores all the genetic information for an entire living organism
Single cell like an amoeba
Multi cell like a human

6. Why do we study DNA? We study DNA for many reasons:
its central importance to all life on Earth
medical benefits such as cures for diseases
better food crops.
About better food crops, this area is controversial. There is a Dr. Charles Arntzen who is working on bioengineering foods with vaccines in them. People in poor countries could be immunized against diseases just by eating a banana, for instance.

7. Chromosomes and DNA Chromosomes are made up of genes.
Genes are made up of a chemical called DNA.
{Ask students where the chromosomes are in this picture. Or ask them where the DNA is. Remind them that the mitochondria also have DNA.}

8. One Strand of DNA
The backbone of the molecule is alternating phosphate and deoxyribose, a sugar, parts.
The teeth are nitrogenous bases.
phosphate
deoxyribose
{Point to the 3-D mode, if you have one, to show the parts as you discuss them.}
bases

9. Nucleotides
O -P O O
One deoxyribose together with its phosphate and base make a nucleotide.
O -P O O
Nitrogenous
base C O
Phosphate
{Ask students where they have seen a similar molecule before in this class.
Answer: ATP Emphasize that nucleotides are the basic building blocks or units of a DNA molecule and that a single molecule has many millions of nucleotides.} C C C
Deoxyribose
ribose O

10. Do Now! Where is DNA located? What does it look like?
What are its bases?
Why do you think DNA is located there?

11. DNA by the numbers Each cell has about 2 m of DNA.
The average human has 75 trillion cells.
The average human has enough DNA to go from the earth to the sun more than 400 times.
DNA has a diameter of only m.
The earth is 150 billion m
or 93 million miles from
the sun.
If you unravel all the DNA in the chromosomes of one of your cells, it would stretch out 2 meters. If you did this to the DNA in all your cells, it would stretch from here to sun more than 400 hundred times!

12. What’s the main difference between DNA and RNA

13. RNA
In RNA Thymine is replaced by Uracil
A-U (RNA)
not
A-T (DNA)

14. IF the DNA strand is GTACCAGATTAGC
What would the RNA strand be?

15. Transcription
When a secretary transcribes a speech, the language remains the same. However, the form of the message changes from spoken to written

16. Transcription
Transcription- RNA is made from a DNA template in the nucleus.
This type of RNA is called messenger RNA or mRNA
When a reporter transcribes a speech, the language remains the same. However, the form of the message changes from spoken to written

17. Transcription DNA is protected inside the nucleus.
mRNA carries the message of DNA into the cytoplasm to the ribosome's

19. Translation To translate English into Chinese requires an interpreter.
Some person must recognize the worlds of one language and covert them into the other.

20. tRNA Transfer RNA The cells interpreter
tRNA translated the three-letter codons of mRNA to the amino acids that make up protein.

21. Codon The flow of information from gene to protein is based on codons.
A codon is a three-base word that codes for one amino acid

22. Information Flow: DNA to RNA to Protein

23. Genetics The study of heredity, how traits are passed from parent to offspringor x = or

24. What is it?! Genetics is the study of genes.
Inheritance is how traits, or characteristics, are passed on from generation to generation.

25. Chromosomes are made up of genes, which are made up of DNA.
Genetic material (genes, chromosomes, DNA) is found inside the nucleus of a cell.
Gregor Mendel is considered “The Father of Genetics"

26. Genetics
Small sections of DNA are responsible for a “trait”. These small sections are called “Genes”.
Gene - A segment of DNA that codes for a specific trait
Trait - A characteristic an organism can pass on to it’s offspring through DNA
Gene

27. Genetics Hair color is a perfect example of a trait
What color hair should their children have?
Prince Charming is blond
Snow White has dark hair

28. Genetics There are three basic kinds of genes:
Dominant - A gene that is always expressed and hides others
Recessive - A gene that is only expressed when a dominant gene isn’t present
Codominant - Genes that work together to produce a third trait

29. Genetics Dominant and Recessive Genes
A dominant gene will always mask a recessive gene.
A “widows peak” is dominant, not having a widows peak is recessive.
If one parent contributes a gene for a widows peak, and the other parent doesn’t, the off spring will have a widows peak.
Widows Peak

30. T,t TT, tt Tt, Gg TERMS TO KNOW ALLELES HOMOZYGOUS HETEROZYGOUS
DIFFERENT FORMS OF A TRAIT THAT A GENE MAY HAVE
T,t
HOMOZYGOUS
AN ORGANISM WITH TWO ALLELES THAT ARE THE SAME
TT, tt
HETEROZYGOUS
AN ORGANISM WITH TWO DIFFERENT ALLELES FOR A TRAIT
Tt, Gg

31. Tt, Gg T OR G t or g TERMS TO KNOW HYBRID DOMINANT RECESSIVE
SAME AS HETEROZYGOUS
Tt, Gg
DOMINANT
A TRAIT THAT DOMINATES OR COVERS UP THE OTHER FORM OF THE TRAIT
REPRESENTED BY AN UPPERCASE LETTER
T OR G
RECESSIVE
THE TRAIT BEING DOMINATED OR COVERED UP BY THE DOMINATE TRAIT
REPRESENTED BY A LOWER CASE LETTER
t or g

32. TERMS TO KNOW PHENOTYPE TALL, SHORT, GREEN, WRINKLED GENOTYPE
THE PHYSICAL APPEARANCE OF AN ORGANISM
(WHAT IT LOOKS LIKE)
TALL, SHORT, GREEN, WRINKLED
GENOTYPE
THE GENE ORDER OF AN ORGANISM
(WHAT ITS GENES LOOK LIKE)
TT, GG, Tt, gg
Gg, tt
RATIO
THE RELATIONSHIP IN NUMBERS BETWEEN TWO OR MORE THINGS
3:1, 2:2, 1:2:1

33. Gregor Mendel Austrian Monk. Experimented with “pea plants”.
Used pea plants because:
They were available
They reproduced quickly
They showed obvious differences in the traits
Understood that there was something that carried traits from one generation to the next.

34. Mendel’s Pea Plants
Mendel based his laws on his studies of garden pea plants. Mendel was able to observe differences in multiple traits over many generations because pea plants reproduce rapidly, and have many visible traits such as:
Pod color
Seed Color
Plant Height
Green
Yellow
Green
Yellow
Seed Shape
Short
Pod Shape
Tall
Wrinkled
Round
Smooth
Pinched

35. What is meant by “true breeding?”
To test the hypothesis, Mendel crossed true-breeding plants that had two distinct and contrasting traits—for example, purple or white flowers.
What is meant by “true breeding?”
Mendel cross-fertilized his plants by hand. Why is it important to control which plants would serve as the parents?

36. Mendel’s Experiments
Mendel noticed that some plants always produced offspring that had a form of a trait exactly like the parent plant. He called these plants “purebred” plants.
EXAMPLE: -purebred short plants always produced short offspring purebred tall plants always produced tall offspring. X
Short Offspring
Purebred Short Parents X
Purebred Tall Parents
Tall Offspring

37. Mendel’s First Experiment
Mendel crossed purebred plants with opposite forms of a trait. He called these plants the parental generation , or P generation. For instance, purebred tall plants were crossed with purebred short plants. X
Parent Short P generation
Parent Tall P generation
Offspring Tall F1 generation
Mendel observed that all of the offspring grew to be tall plants. None resembled the short short parent. He called this generation of offspring the first filial , or F1 generation, (The word filial means “son” in Latin.)

38. Mendel’s Second Experiment
Mendel then crossed two of the offspring tall plants produced from his first experiment.
Parent Plants
Offspring X
Tall F1 generation
3⁄4 Tall & 1⁄4 Short F2 generation
Mendel called this second generation of plants the second filial, F2, generation. To his surprise, Mendel observed that this generation had a mix of tall and short plants. This occurred even though none of the F1 parents were short.

39. Mendel studies seven characteristics in the garden pea

40. Martin Sheen
Charlie Sheen
How is it possible to maintain such genetic continuity?
Kirk
Kirk Douglas
Michael
Emilio Estevez