1. Genetics Study Guide

2. Passing of traits from parent to offpsring
What is Heredity?

3. Different forms of a characteristic
What is a trait?

4. Forms of a gene
What is an allele?

5. Traits are controlled by
define
example
Single Genes
2 alleles
Freckles
Multiple Alleles
2 or more alleles control a single trait
Blood type
Many Genes
2 or more genes control a trait
Skin color
Sex-Linked
Alleles for a trait are on the sex chromosomes
Color blindness
Incomplete Dominance
Blend together
Pink flower
Co-dominance
Alleles work together; both appear
AB blood type

6. Compare genotype and phenotype
Genotype: 2 or more alleles control a trait
Ex. TT, Tt,tt
Phenotype: physical appearance of a trait
Ex. Blond hair, green eyes
Compare genotype and phenotype

7. Homozygous/purebred: 2 same alleles
Heterozygous/hybrid: 2 different alleles
Compare homozygous and heterozygous genotypes. Include purebred and hybrid

8. What is a Punnett Square?
A tool used to predict the outcome of a genetic cross
What is a Punnett Square?

9. Complete the following genetic crosses

10. List the genotypes and phenotypes for the crosses above:
Tt: tall 100%
TT: tall 50%
Tt: tall 50%
TT: 25%
Tt: 50%
tt: 25%
List the genotypes and phenotypes for the crosses above:

11. A diagram that shows the inheritance of a trait through a family
What is a pedigree?

12. Given the genotypes, describe the phenotypes:
AA=normal
Aa=normal
aa= albino
Given the genotypes, describe the phenotypes:

13. 1. aa
2. Aa
3. Aa
4. Aa
5. aa
Fill out the pedigree

14. 3 children
All female
How many children does the family have? What are the sexes of the children?

15. How many males are albino? Females?

16. What is a genetic disorder?
A disease caused by an abnormality in DNA
What is a genetic disorder?

17. What causes a genetic disorder?
A mutation or change in DNA
What causes a genetic disorder?

18. What makes a mutation harmful?
If it decreases the chances of an organism surviving and/or reproducing.
What makes a mutation harmful?

19. What is a karyotype? What is it used for?
A picture of a person’s chromosomes. It is used to diagnose some genetic disorders.
What is a karyotype? What is it used for?

20. How many chromosomes do human have in each cell?
46 in body cells, 23 in sex cells
How many chromosomes do human have in each cell?

21. The division of sex cells
What is meiosis

22. What are the results of meiosis?
4 cells with half the number of chromosomes
What are the results of meiosis?

23. What are the sex chromosomes for males? Females?
Males: XY
Females: XX
What are the sex chromosomes for males? Females?

24. A twisted double helix (ladder) that contains the genetic information for an organism
What is DNA?

25. Where is DNA found in a eukaryotic cell?
In the nucleus
Where is DNA found in a eukaryotic cell?

26. A twisted ladder
What does DNA look like?

27. TTGACAT
What would the complimentary nucleic acids be for AACTGTA in a strand of DNA?

28. How do selective breeding and genetic engineering differ?