1. CH 10, 11 & 12
Final Exam Review

2. Homologous Chromosomes
Pairs of chromosomes having DNA segments, or genes, for the same traits
Gene is a segment of DNA

3. Genotype tall allele - T, is dominant to the short allele – t
Possible Genotypes:
TT - Tall
Tt – Tall – Heterozygous (HYBRID)
tt – Short

4. Possible Gametes
Parent YyRr
Remember FOIL
YR Yr yR yr

5. Anaphase 1 - Meiosis Tetrad is being pulled apart by Spindle Fibers.
Spindle fibers move the chromosomes.
The number of chromosomes decrease from diploid (2n) to haploid (n).

6. Asexual Reproduction one parent no union of gametes
offspring genetically identical to the parent
Example – Binary Fission

7. Crossing Over

8. Meiosis – Metaphase 1 or 2? Metaphase 2
Because we do not see a tetrad anymore.

9. Fertilization
The offspring that would result from this egg and sperm would be a FEMALE (XX)

10. Recessive vs. Dominant Parents are Dominant Bb x Bb (HE)
Children could be:
BB: Brown (Dominant)
Bb: Brown (Dominant)
bb: Blue
All you need is one dominant allele to show the dominant trait.

11. Codominance Blood Type Roan Cow – Patches of Red and White Fur
Type A - IA IA or IAi
Type B - IB IB or IBi
Type AB - IA IB
Type O - ii
Roan Cow – Patches of Red and White Fur
YOU SEE BOTH PHENOTYPES not a mixture.

12. Nondisjunction When tetrads of sister chromatids fail to separate
Can cause disorders with extra or not enough chromosomes.
Down Syndrome – Trisomy 21
Extra chromosome 21

13. Polygenic Inheritance
Multiple genes control a single trait
Height
This is why you can have to normal parents with
A normal height child
A really tall child
A really short child
Skin Color

14. Recessive Sex – linked traits
Usually seen in males
Because they only have one X chromosome
Xb Xb - Colorblind Female
XB Xb – Normal Female
XB XB - Normal Female
Xb Y – Colorblind Male
XB Y – Normal Male

15. Incomplete Dominance Mixture of the traits (similar to Blended)
Red x White = Pink

16. Incomplete Dominance If we cross 2 pink flowers we get: 25% Red
25% White

17. Classify
Carriers (II -1 & II -4)
Relationships

18. Classify Last set of parents in generation II – must be carriers
Mom in generation also had to be a carrier

19. Disorders to know! Achondroplasia Albinism Cystic fibrosis
stunts growth to a maximum of 1.2 m
Albinism
an absence of pigments in the skin, hair, and eyes
Cystic fibrosis
prevents cells from absorbing chloride ions, thus producing extra mucus
Down syndrome
Extra Chromosome 21 (Trisomy)
Huntington’s disease
this disorder can result in uncontrolled movements

20. Karyotype
Trisomy 21
Down Syndrome
Male X & Y

21. People Griffith Watson & Crick
Determined that the bacteria had changed forms (because DNA was transferred = genetic material)
Watson & Crick
Came up with the structure of DNA (double helix)

22. Structure
Nucleotide
Phosphate
Sugar
Nitrogen Base

23. DNA Replicaiton A – T C – G Purine pairs with a Pyrimidine
Notice no Uracil

24. Transcription A – U C – G Thymine is not present in RNA Example
ATC TGA CCG = DNA
UAG ACU GGC = RNA

25. Translation
3 base pairs
AUC – Isoleucine
GGG - Glycine