warm ups march 2 nd, 2012 what is a punnett square used for? what are the parental generation,...
DESCRIPTION
O T T F F S S E __ It ’ s EASY if you know the PATTERN! (Just like Punnett Squares) NENE WOWO HREEHREE OUR OUR IVEIVE IXIX EVENEVEN IGHTIGHT 9 NINENINETRANSCRIPT
Warm ups – March 2nd, 2012
• What is a Punnett square used for?• What are the parental generation, first filial, and
second filial generations symbolized by?• If fluorescent red eye color was dominant, and
white was recessive,and you crossed a red-eyed rat with a white-eyed rat, IN WHAT GENERATION would you first see the white-eyed trait appear?
O T T F F S S E __
What comes next?
O T T F F S S E __
It’s EASY if you know the PATTERN!(Just like Punnett Squares)
NE
WO
1 2 3 4 5 6 7 8
HREE
OUR
IVE
IX
EVEN
IGHT
9NINE
PROBABILITY & PUNNETT SQUARES
11-2
Go to Section:
Tossing CoinsIf you toss a coin, what is the probability of getting heads? Tails? If you toss a coin 10 times, how many heads and how many tails would you expect to get? Working with a partner, have one person toss a coin 50 times while the other person tallies the results on a sheet of paper. Then, switch tasks to produce a separate tally of the second set of 50 tosses. Add your results together to get a percentage heads or tails.
Section 11-2
Interest Grabber
It can be written as a:Fraction ____
Percent ____Ratio ____
____________________is the __________ that a
particular _________________
PROBABILITY
1/425%
1:3
likelihoodevent will occur
COIN FLIPThere are 2 possible
outcomes:HEADS TAILS
capital
http://www.arborsci.com/CoolStuff/CoinFlip.jpg
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.
1/2 50% 1:1
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.
PAST DON’T FUTURE
Probability best predictinglarge
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 =______
capital
lower-case
Tt NOT S for short
Dominant
Recessive
HOMOZYGOUSHETEROZYGOUS
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: ____HETEROZYGOUS HYBRID
HOMOZYGOUS PURESAME
TT tt
DIFFERENT
Tt
PHENOTYPE/GENOTYPEThe ________________ of an organism
is its _____________
The ____________of an organism isits _____________
GENOTYPE
PHENOTYPE
genetic makeup
appearance
MAKING A CROSS for only a __________ trait =____________________
A Punnett square for a MONOHYBRID CROSS looks like this:
MONOHYBRID CROSSONE GENE
PUNNETT SQUARESare used to show possible offspring
from a cross between 2 parents
_______________ go at top and on left side
Boxes show _______________________________
T T
T
tpossible offspring combinations
Parent alleles
1. ___________ what _________________ are2. ________correct__________ square __________3. ______ possible_______________________4. ______ boxes with _____________________5. Determine ____________of_____________& ____________
STEPS FOR MAKING CROSSES
Figure out parent allelesChoose Punnett sizePut in parent gametesFill in offspring combinations probabilities phenotypes
genotypes
IN PEA PLANTSTall is dominant over short TALL = ____
SHORT = ____T
tLET’S MAKE A CROSS!
PURE TALL PURE SHORTX
PURE TALL parentWhat are the parent alleles?
T T _________
T T
HOMOZYGOUS
What gametes can it make?
PURE SHORT parent What are the parent alleles?
t t _________
t t
HOMOZYGOUS
What gametes can it make?
GENOTYPE _____ PHENOTYPE _______
_____ of the offspring
____ % ___/4 will be
T T
t
t
T t T t
T t T tTt TALL
ALL
1004
HYBRID TALL parent What are the parent alleles?
T t _________
T t
HETEROZYGOUS
What gametes can it make?
GENOTYPES¼ = _____½ = _____¼ = _____
T t
T
t
T T T t
T t t t
PHENOTYPES ____ or ____% _________ ____ or ____% _________
TT
75
Tttt
3/41/4 SHORT
TALL25
PRACTICE MAKING GAMETES for a MONOHYBRID CROSS
Tall = ____ Round seeds = ___ Short = ____ Wrinkled seeds = ___
Tt
Rr
Homozygous Tall parent =
What gametes can it produce?
What are the possible gametes?
T T
T T
PURE wrinkled parent =
What gametes can it produce?
What are the possible gametes?
rr
r r
Heterozygous Round parent =
What gametes can it produce?
What are the possible gametes?
R r
R r
Hybrid Tall parent =
What gametes can it produce?
What are the possible gametes?
Tt
T t