What makes you….you!

What type of cells are these?What type of cells are these?

What is the arrow pointing to?What is the arrow pointing to?

Video: Cracking the Code of Life | Watch NOVA Online | PBS Video

1800’s – with discovery of microscope, scientists realized something [DNA] existed in the nucleus

1950’s – Rosalind Franklin- using X-ray discovered a stand of DNA consists of a “double helix” or spiral shaped ladder

- Watson and Crick- “ sides of ladder” consists of sugars and phosphates and “steps of ladders” are nitrogen base pairs

DNA- [Deoxyribonucleic Acid] threads of chromatin

Shape - like a spiral ladder

1. Rungs = Pairs of Nitrogen Bases A-T = Adenine - Thymine G-C = Guanine - Cytosine 2. Handrails = Alternating Phosphate and Deoxyribose Sugar

* Base pairs always attached to sugar

Sugar

phosphate

Nitrogen base

Gene - a section of DNA coil, determines traits of organism

Inside the NucleusInside the Nucleus

Heredity- passing of genes from parent > offspring

The Human Genome Project, 3D Animation - YouTube

Alleles - different forms a gene may have for a trait

Genetics- study of how alleles affect generations of offspring

Chromosome Number of Base Pairs [millions]

1 279

2 251

3 221

4 197

5 198

6 176

7 163

8 148

9 140

10 143

11 148

12 142

13 118

14 107

15 100

16 104

17 88

18 86

19 72

20 66

21 45

22 48

X / Y 163 / 51

Total BasePairs = 3.2 billion

Total Genes = 30,000

98% of genes for Humans & Chimps are alike

Genes between Humans only differ by 0.01%

To read all 3.2 billionbase pairs aloud -it would take 9.5 years

A-T-C-A-T-T-C-T-G

http://app.discoveryeducation.com/search?Ntt=mutations

http://app.discoveryeducation.com/search?Ntt=mutations

http://www.youtube.com/watch?v=RjsU_rJpTWg

http://www.youtube.com/watch?v=-EwtyO16dFg

One comes from mom, one from Dad

MomDad

Eye color

Genetic Cross- random pairing of one gene from each parent

Gregor Mendel = Father of GeneticsGregor Mendel = Father of Genetics

Dominant- “what is seen” [Capital letter]

Recessive- “what is hidden” [Lower case letter]

Phenotype- physical trait that appears ex: Tall

Genotype- genetic make-up or letters ex: TT

Homozygous [homo means same, zygous means pair] = TT, tt

Heterozygous [hetero means different, zygous means pair] = Tt

Dominant Traits

1. Tongue roller2. Hand clasp3. Unattached earlobe 4. Straight Pinky 5. Hairy finger- 2nd section6. Dimples7. Cleft Chin8. Straight hair line9. Freckles10. Hitch hiker thumb11.Brown eyes12. Second toe longer than big toe13. Finger divide- 2 vs 114. PTC

Punnett Squares- visual tool used to display the possibilities of a genetic cross

Mom’s Traits

Dad’s

T ra i t s

For For the Wisconsin Fast plant, purple stems are dominate to green stems. After growing several hundred plants, Johnny realizes that 75% of the offspring have purple stems and 25% of the offspring have green stems.

Find the genotypes of the parents using a Punnett square.

1. What are the steps of the DNA ladder made of?

Nitrogen Base Pairs : A-T, G-C

2. What are the sides of the ladder made of? Phosphates and sugars

3. What are base pairs always attached to? Sugar

4. Where are genes located? On chromosomes

5. Different forms of the same genes are called? Alleles

6. Physical appearance of a trait is called? Phenotype

7. Genetic make up of an organism? Genotype

8. What does the term heterozygous mean? Homozygous? Different gene combinations, dominant and recessive Same gene pairs

9.What is a mutation? Are they always harmful? Permanent change to an organism No create variety

10. What is the purpose of using a Punnett square? Determine probability of traits that can be inherited

11. What is the process that involves one cell dividing two times to create four new cells with half the number of chromosomes? Meiosis

12. What type of cells undergo meiosis? Sperm and Egg

13.How many chromosomes are in a human egg cell? 23 ----- Why not 46?

14.What is it called when many genes create ONE trait? polygenic inheritance

15. What is the term for more than two possibilities of a trait?

multiple alleles

16. When both genes are expressed equally for a trait it is called? incomplete dominance

Creation of ProteinsCreation of Proteins

Base pairs form amino acids which link together to form proteins