Genetics - Test 2 Review Sheet

1. Patterns of Inheritance
a) Mendel's experiments (F1, F2, P generations)
b) Define: gene, allele, chromosome, heritable, character, trait, punnett, dominant, recessive, homozygous, heterozygous, true-breeding, genotype, phenotype
c) Perform monohybrid and dihybrid crosses (9:3:3:1)
d) Compare the particulate theory of inheritance to the blending theory
e) List (and understand) Mendel's Principles
f) Understand the relationship between alleles and chromosomes
g) Test cross - when are they used and what do they tell us
h) Test will include a variety of Mendelian genetics problems (Tt x Tx, Pp x pp….. etc)

2. Advanced Crosses
a) Solve multiple allele traits such as Labrador retriever genetics or blood types
b) Solve problems involving codominance and incomplete dominance
c) Define: polygenic, sex-linked, quantitative inheritance, lethal alleles, epistatic alleles, pleiotropy, wild type vs mutant alleles,
d) Solve problems involving sex linked genes
e) Solve advanced problems that can combine various allele types (codominance and lethality for example)
f) Linkage group problems
g) Interpret pedigrees
h ) Understand the uses for a chi square analysis

4. Human Genetic Diseases (causes, affects, treatments, underlying genetics)
" Hemophilia | Tay Sachs | Achondroplasia | Cystic Fibrosis | Colorblindness

6. Hardy Weinberg Equation and Population Genetics
" Given formula, determine allele frequencies of populations
" How does the Hardy Weinberg equation help to show evolutionary trends

7. How does Cloning work?
" Artificial embryo twinning
" Somatic Cell Nuclear Transfer
" Natural Cloning
" Gene cloning
" Be able to label, describe or interpret a cloning diagram
" Uses for cloning

8. Recombinant DNA Technology (transgenic organisms)
" Plasmids | Restriction enzymes | Sticky vs blunt ends | Uses for technology

10. DNA Fingerprinting - know the steps
" Restriction Enzymes | Southern Blots | PCR | RFLP
" Gel Electrophoresis
" Interpreting DNA fingerprints (from image)
13. Stem Cells - what are they and why is the research important?
" Differentiation
" Adult stem cells versus embryonic stem cells
" Potential uses of stem cells
" Ethical Considerations


SAMPLE PROBLEMS:

1. Monohybrid Cross: A plant that is heterozygous for the tall gene is crossed with one that is recessive and short. What are the phenotypes of the offspring and in what proportion?

2. Dihybrid Cross: In plants, round seeds is dominant to wrinkled seeds and tall is dominant to short. Show the cross between two plants that are heterozygous for both traits. What are the phenotypes of the offspring and in what proportion?


b. What if the second parent was recessive for both traits? What phenotypes would you expect in the offspring?


3. Epistatic Cross: In Labradors, the yellow coat color is epistatic. Labs can be black (dominant), brown (recessive) or yellow which is caused by a pair of recessive alleles (yy) A heterozygous black lab (BbEe) is crossed with a yellow lab (Bbee). What proportion of the offspring will be black? _________ Yellow? __________ Brown? __________


4. Codominance: In cattle, coat color can be red or white. If a red cow is crossed with a white cow, the offspring is a mottled red & white - coloration farmers call "roan". What phenotypes would you get from a cross between a roan and a white cow?

5. Blood types: If one parent has type A blood and another parent has type B blood, what are ALL the possible blood types of the children. You do not know the parents' genotypes.


6. Sex Linked: In humans, colorblindness is a sex linked, recessive trait. If a woman who is a carrier for colorblindness marries a colorblind man, what are the chances that their children will be colorblind?


7. Linkage Group: In fruit flies, the gene for dumpy wings (recessive) is on the same chromosome as the gene for short antennae. If a heterozygous fly (DdAa) is crossed with one that is recessive for both traits (ddaa) are crossed, what are the phenotypes of the offspring and in what proportion? On the first fly, the dominant genes are located on the SAME chromosome.

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