1. GENETICS PRACTICE

2. R r Y y WHAT ARE THE POSSIBLE GAMETES THIS PARENT CAN MAKE?
HETEROZYGOUS ROUND YELLOW
Each gamete should get one of each kind of gene
R r Y y
___________ ____________ _____________ _____________

3. PRACTICE MAKING GAMETES
WHAT ARE THE POSSIBLE GAMETES
THIS PARENT CAN MAKE?
HETEROZYGOUS ROUND YELLOW
Each gamete should get one of each kind of gene
R r Y y
R Y
r y
r Y
R y
___________ ____________ _____________ _____________

4. Sign of a ______________________ cross is a RY Ry rY ry
____ Round & Yellow
____ Round & green
____ Wrinkled & yellow
____ wrinkled & green RY Ry rY ry
RRYY RRYy RrYY RrYy RRYy RRyy RrYy Rryy RrYY RrYy rrYY rrYy
RrYy Rryy rrYy rryy
Sign of a ______________________ cross is a
_____________ ratio in offspring.

5. heterozygous dihybrid 9:3:3:1RY Ry rY ry
____ Round & Yellow
____ Round & green
____ Wrinkled & yellow
____ wrinkled & green 9 RY Ry rY ry
RRYY RRYy RrYY RrYy RRYy RRyy RrYy Rryy RrYY RrYy rrYY rrYy
RrYy Rryy rrYy rryy 3 3 1
heterozygous dihybrid
Sign of a ______________________ cross is a
_____________ ratio in offspring.
9:3:3:1

6. __________ratio is a clue that it’s a _________________________cross9
____ ____________ TRAIT 1 ; ____________ TRAIT 2
____ ____________ TRAIT 1; _____________ TRAIT 2
____ ____________ TRAIT 1; _____________ TRAIT 2
dominant dominant 3
dominant recessive 3
recessive dominant 1
recessive recessive
__________ratio is a clue that it’s a
_________________________cross
9:3:3:1
HETEROZYGOUS TWO gene
(DIHYBRID)

7. What is the probability?
AaBBCcdd parent genome What is the probability of producing a gamete with this gene combination? ABCd _____________________________ AbCd ______________________________ abcd _______________________________

8. What is the probability?
AaBBCcdd X AabbCCDd parents What is the probability of producing a offspring with this gene combination? AABbCcDd _____________________________ AaBBccdd______________________________ aaBbccDd_______________________________

9. What is the probability?
AaBBCcdd parent genome What is the probability of producing a gamete with this gene combination? ABCd _____________________________ Abcd ______________________________ Abcc _______________________________

10. What is the probability?
AaBBCcdd X AabbCCDd parents What is the probability of producing a offspring with this gene combination? AABbCcDd _____________________________ AaBBccdd______________________________ aaBbccDd_______________________________

11. PEDIGREES
= male; doesn’t show trait = female; doesn’t show trait = shows trait = carrier; doesn’t show trait

12. Write the genotype of each individual next to the symbol.
Is it possible that this pedigree is for an autosomal recessive trait?
 Is it possible that this pedigree is for an X-linked recessive trait?

13. The following is a pedigree of Dwarfism.
Is this trait inherited as AUTOSOMAL OR X-LINKED? DOMINANT or RECESSIVE?
Fill in the genotypes for A, B, C, and D

14. The inheritance of the disorder in II-3 from his father rules out what form of inheritance?

15. Is this trait inherited as AUTOSOMAL OR X-LINKED? DOMINANT or RECESSIVE?

16. Write the genotype of each individual next to the symbol.
b) Is it possible that this pedigree is for an autosomal recessive trait? EXPLAIN YOUR ANSWER
c) In this pedigree, two generations have been skipped. What can you conclude about recessive traits skipping generations?

19. A Wild type fruit fly (heterozygous for gray body and normal wings) is mated with a black fly with vestigial wings.
OFFSPRING: wild type 785- black-vestigial 158- black- normal wings 162- gray body-vestigial wings
Is it 9:3:3:1?
Is it 3 Wild type : 1 black vestigial?

20. A Wild type fruit fly (heterozygous for gray body and normal wings) is mated with a black fly with vestigial wings.
OFFSPRING: wild type 785- black-vestigial 158- black- normal wings 162- gray body-vestigial wings

21. A Wild type fruit fly (heterozygous for gray body and normal wings) is mated with a black fly with vestigial wings.
OFFSPRING: wild type 785- black-vestigial 158- black- normal wings 162- gray body-vestigial wings
What is the recombination frequency between these genes?

23. A Wild type fruit fly (heterozygous for gray body and normal wings) is mated with a black fly with vestigial wings.
OFFSPRING: wild type 785- black-vestigial 158- black- normal wings 162- gray body-vestigial wings
What is the recombination frequency between these genes?

24. A Wild type fruit fly (heterozygous for gray body and normal wings) is mated with a black fly with vestigial wings.
OFFSPRING: wild type 785- black-vestigial 158- black- normal wings 162- gray body-vestigial wings
What is the recombination frequency between these genes?

25. A Wild type fruit fly (heterozygous for gray body and red eyes) is mated with a black fly with purple eyes.
OFFSPRING: gray body/red eyes black body/purple eyes 49- gray body/purple eyes 45- black body/red-eyes
What is the recombination frequency between these genes?

26. A Wild type fruit fly (heterozygous for gray body and red eyes) is mated with a black fly with purple eyes.
OFFSPRING: gray body/red eyes black body/purple eyes 49- gray body/purple eyes 45- black body/red-eyes
What is the recombination frequency between these genes?

27. A Wild type fruit fly (heterozygous for gray body and red eyes) is mated with a black fly with purple eyes.
OFFSPRING: gray body/red eyes black body/purple eyes 49- gray body/purple eyes 45- black body/red-eyes
What is the recombination frequency between these genes?

28. Determine the sequence of genes along a chromosome based on the following recombination frequencies
A-D 10%
B-C 15%
B-D 5%

29. Determine the sequence of genes along a chromosome based on the following recombination frequencies
A-D 10%
B-C 15%
B-D 5%

30. Determine the sequence of genes along a chromosome based on the following recombination frequencies
A-D 10%
B-C 15%
B-D 5%

31. Determine the sequence of genes along a chromosome based on the following recombination frequencies
A-D 30%
B-C 24%
B-D 16%

32. Determine the sequence of genes along a chromosome based on the following recombination frequencies
A-D 30%
B-C 24%
B-D 16%

33. Determine the sequence of genes along a chromosome based on the following recombination frequencies
A-D 30%
B-C 24%
B-D 16%
CABD

34. Determine the sequence of genes along a chromosome based on the following recombination frequencies
A-B 8%
A-C 28%
A-D 25%
B-C 20%
B-D 33%

35. Determine the sequence of genes along a chromosome based on the following recombination frequencies
A-B 8%
A-C 28%
A-D 25%
B-C 20%
B-D 33%

36. Determine the sequence of genes along a chromosome based on the following recombination frequencies
A-B 8%
A-C 28%
A-D 25%
B-C 20%
B-D 33%

37. Sign of a ______________________ cross is a RY Ry rY ry
____ Round & Yellow
____ Round & green
____ Wrinkled & yellow
____ wrinkled & green 9
RRYY RRYy RrYY RrYy
RRYy RRyy RrYy Rryy RrYY RrYy rrYY rrYy RrYy Rryy rrYy rryy RY Ry rY ry 3 3 1
heterozygous dihybrid
Sign of a ______________________ cross is a
_____________ ratio in offspring.
9:3:3:1

39. aabbccdd ______________________________
The genotype of F1 individuals in a tetrahybrid cross is
AaBbCcDd X AaBbCcDd
Assuming independent assortment of these four genes, what are the probabilities that F2 offspring will have the following genotypes?
aabbccdd ______________________________
AaBbCcDd ______________________________
AaBBCCdd ______________________________