1. PROBABILITY & PUNNETT SQUARES 11-2

2. ____________________ is the __________ that a particular _________________
It can be written as a:
Fraction ____
Percent ____
Ratio ____

3. COIN FLIP capital There are 2 possible outcomes: HEADS TAILS
COIN FLIP
There are 2 possible outcomes:
HEADS TAILS
capital
The chance the coin will land on either one is:
____ ____ ____
Alleles segregate randomly just like a coin flip. . . So can use probability to predict outcomes of genetic crosses.

4. PROBABILITIES _____ outcomes ______ affect _________ones
_____________works ______ in ___________ a ________ number of events.
If last coin flip was heads… there is still a 50/50 chance the next flip will be heads too.
The more flips. . . The closer results will be to
the expected 50:50 average.

5. DOMINANT/RECESSIVE
_____________ allele is represented by a ____________ letter. (usually the first letter of the trait)
____________ allele is represented by the SAME
_________________ letter.
EX: Tall = ______
Short =______

6. HOMOZYGOUS HETEROZYGOUS
When both alleles in the pair are the _______, the organism is _______________ or __________
EX: ____ or ___
When both alleles in the pair are _____________, the organism is
_________________ or _____________
Ex: ____

7. PHENOTYPE/GENOTYPE
The ________________ of an organism is its _____________
The ____________of an organism is
its _____________

8. MAKING A CROSS for only a __________ trait = ____________________
A Punnett square for a MONOHYBRID CROSS looks like this:

9. PUNNETT SQUARES
are used to show possible offspring from a cross between 2 parents
_______________ go at
top and on left side
Boxes show ____________ ___________________
T T T t

10. STEPS FOR MAKING CROSSES
1. ___________ what _________________ are
2. ________correct__________ square __________
3. ______ possible_______________________
4. ______ boxes with _____________________
5. Determine ____________of_____________& ____________

11. TALL = ____ SHORT = ____ IN PEA PLANTS Tall is dominant over short
LET’S MAKE A CROSS!
PURE TALL PURE SHORT

12. PURE TALL parent What are the parent alleles? 
What gametes
can it make?

13. PURE SHORT parent What are the parent alleles? 
What gametes
can it make?

14. _____ of the offspring ____ % ___/4 will be
GENOTYPE _____ PHENOTYPE _______

15. HYBRID TALL parent What are the parent alleles? 
What gametes
can it make?

16. GENOTYPES ¼ = _____ ½ = _____ PHENOTYPES ____ or ____% _________

17. PRACTICE MAKING GAMETES for a MONOHYBRID CROSS
Tall = ____ Round seeds = ___
Short = ____ Wrinkled seeds = ___

18. What are the possible gametes?
Homozygous Tall parent =
What gametes can it produce?  

19. What are the possible gametes?
PURE wrinkled parent =
What gametes can it produce?  

20. What are the possible gametes?
Heterozygous Round parent =
What gametes can it produce?  

21. What are the possible gametes?
Hybrid Tall parent =
What gametes can it produce?  