1. What type of cells are these?

2. Discovering - DNA
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
Video: Cracking the Code of Life | Watch NOVA Online | PBS Video

3. DNA DNA- [Deoxyribonucleic Acid] threads of chromatin
phosphate
DNA- [Deoxyribonucleic Acid]
threads of chromatin
Sugar
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
Nitrogen
base

4. Inside the Nucleus Gene - a section of DNA coil, determines traits
of organism
Heredity- passing of genes from parent > offspring

5. Alleles - different forms a gene may
have for a trait
Genetics- study of how alleles affect generations of
offspring

6. Number of Base Pairs [millions]
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 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
98% of genes for Humans & Chimps
are alike
Total Base
Pairs =
3.2 billion
Total
Genes =
30,000
Genes between Humans only differ by 0.01%
To read all
3.2 billion
base pairs aloud -it would take 9.5 years
The Human Genome Project, 3D Animation - YouTube

7.
Mutations
A-T-C-A-T-T-C-T-G

8. Making Proteins
A-T-C-A-T-T-C-T-G

9. Mutations

10. Down’s Syndrome

11. Seedless Grapes? Grafting/Cuttings
Grafting/Cuttings

12. Meiosis

13. Alleles One comes from mom, one from Dad Chromosome Dad Mom Eye color
Gene

14. Genetic Cross- random pairing of one gene from each parent
Gregor 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

15. Monogenic Inheritance
Dominant Traits
Tongue roller
Hand clasp
Unattached earlobe
Straight Pinky
Hairy finger- 2nd section
Dimples
Cleft Chin
Straight hair line
Freckles
Hitch hiker thumb
Brown eyes
Second toe longer
than big toe
13. Finger divide- 2 vs 1
14. PTC

16. Punnett Squares- visual tool used to display the
possibilities of a genetic cross
Mom’s Traits D a d’ s T r i t

17. Punnett Squares

19. 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.

20. DNA Unit Review 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

21. 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
What is a mutation? Are they always harmful?
Permanent change to an organism
No create variety

22. 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
How many chromosomes are in a human
egg cell?
Why not 46?

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

24. Creation of Proteins Base pairs form amino acids which link together
to form proteins