why Choose the answer that makes the most sense to you and explain why Bb X bb E Bb X Ww BB X Bb F BB X WW Ww X ww G Bb X WW WW X Ww H Ww X bb Using Punnett Squares ID: 777338
Download The PPT/PDF document "Tuesday Bell Work 32. Which of the follo..." is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Tuesday Bell Work
32. Which of the following is an appropriate cross of a heterozygous white bird with a blue one, and
why
?
Choose the answer that makes the most sense to you and explain why
.
Bb X bb E. Bb X
Ww
BB X Bb F. BB X WW
Ww
X
ww
G. Bb X WW
WW X
Ww
H.
Ww
X bb
Slide2Using Punnett Squares
Comans
Science 2014-2015
Slide3How to Do a Punnett Square
Let’s say you get a question like this:
Mendel crossed two heterozygous purple flowered pea plants. What percent of offspring are white flowered?
How can you use a Punnett square to answer such a complicated question?
Slide4How to Do a Punnett Square
Assign a key (what letters you will use).
Mendel crossed two heterozygous purple flowered pea plants. What percent of offspring are white flowered?
How to Do a Punnett Square
Assign a key (what letters you will use).
Mendel crossed two heterozygous purple flowered pea plants. What percent of offspring are white flowered?
We will use a capital letter to represent the dominant trait. What is dominant here?
Slide6How to Do a Punnett Square
Assign a key (what letters you will use).
Mendel crossed
two heterozygous purple
flowered pea plants. What percent of offspring are white flowered?
P = Purple (dominant)
p = White (recessive)
Slide7How to Do a Punnett Square
Assign a key (what letters you will use).
Mendel crossed
two heterozygous purple
flowered pea plants. What percent of offspring are white flowered?
Since both have one of each allele, and both are purple, purple is dominant.
Slide8How to Do a Punnett Square
Set up the cross.
Mendel crossed
two heterozygous purple
flowered pea plants. What percent of offspring are white flowered?
Again, we’ve got one of each allele for each.
Slide9How to Do a Punnett Square
Set up the cross.
Mendel crossed two heterozygous purple flowered pea plants. What percent of offspring are white flowered?
Pp X Pp
Slide10How to Do a Punnett Square
Separate Alleles (set up the Punnett square)
Pp X Pp
Slide11How to Do a Punnett Square
Separate Alleles (set up the Punnett square)
P
p
X
P
p
P
P
p
p
Slide12How to Do a Punnett Square
Separate Alleles (set up the Punnett square)
Pp X Pp
P
P
p
p
Slide13How to Do a Punnett Square
Fill in the Punnett square
Pp X Pp
P
P
p
p
Slide14How to Do a Punnett Square
Fill in the Punnett square
P
p
X
P
p
P
P
p
p
P
P
Slide15How to Do a Punnett Square
Fill in the Punnett square
P
p
X
P
p
P
P
p
p
P
P
P
p
Slide16How to Do a Punnett Square
Fill in the Punnett square
P
p
X
P
p
P
P
p
p
P
P
P
p
P
p
Slide17How to Do a Punnett Square
Fill in the Punnett square
P
p
X
P
p
P
P
p
p
P
P
P
p
P
p
p
p
Slide18How to Do a Punnett Square
Fill in the Punnett square
Pp X Pp
P
P
p
p
PP
Pp
Pp
pp
Slide19How to Do a Punnett Square
List all the genotypes possible (letter combinations in the square)
P
P
p
p
PP
Pp
Pp
pp
PP =
25%
Slide20How to Do a Punnett Square
List all the genotypes possible (letter combinations in the square)
P
P
p
p
PP
Pp
Pp
pp
PP =
25%
Pp =
50%
Slide21How to Do a Punnett Square
List all the genotypes possible (letter combinations in the square)
P
P
p
p
PP
Pp
Pp
pp
PP =
25%
Pp =
50%
pp =
25%
Slide22How to Do a Punnett Square
List all the phenotypes possible (put the genotypes into word description)
PP =
Pp =
pp =
Purple
Purple
White
Slide23How to Do a Punnett Square
Give ratio or percent or fraction for each
PP = 25%, Purple
Pp = 50%, Purple
pp = 25%, White
What are the chances for a Purple flower?
75%
Slide24How to Do a Punnett Square
Give ratio or percent or fraction for each
PP = 25%, Purple
Pp = 50%, Purple
pp = 25%, White
What are the chances for a White flower?
25%
Slide25How to Do a Punnett Square
Go back, read your question, and answer any specific questions
Mendel crossed two heterozygous purple flowered pea plants. What percent of offspring are white flowered?
25%
Slide26Self-Check #1
A rabbit breeder crossed a lop eared rabbit (
Ll
) with another lop eared rabbit (
Ll
). What ratio of offspring have straight ears?
Assign a key (what letters you will use).
L = Lop-eared (dominant)
l = Straight-eared (recessive)
Slide27Self-Check #1
A rabbit breeder crossed a lop eared rabbit (
Ll
) with another lop eared rabbit (
Ll
). What ratio of offspring have straight ears?
Set up the cross.
Ll
X
Ll
Slide28Self-Check #1
A rabbit breeder crossed a lop eared rabbit (
Ll
) with another lop eared rabbit (
Ll
). What ratio of offspring have straight ears?
3. Separate Alleles (set up the Punnett square).
L
L
l
l
Slide29Self-Check #1
A rabbit breeder crossed a lop eared rabbit (
Ll
) with another lop eared rabbit (
Ll
). What ratio of offspring have straight ears?
Fill in the Punnett square
L
L
l
l
Ll
Ll
LL
ll
Slide30Self-Check #1
A rabbit breeder crossed a lop eared rabbit (
Ll
) with another lop eared rabbit (
Ll
). What ratio of offspring have straight ears?
List all the genotypes possible (letter combinations in the square)
LL (25%)
Ll
(50%)
ll
(25%)
Slide31Self-Check #1
A rabbit breeder crossed a lop eared rabbit (
Ll
) with another lop eared rabbit (
Ll
). What ratio of offspring have straight ears?
List all the phenotypes possible (put the genotypes into word description)
LL = Lop-eared
Ll
= Lop-eared
ll
= Straight-eared
Slide32Self-Check #1
A rabbit breeder crossed a lop eared rabbit (
Ll
) with another lop eared rabbit (
Ll
). What ratio of offspring have straight ears?
Give ratio or percent or fraction for each
LL = Lop-eared = 25%
Ll
= Lop-eared = 50%
ll
= Straight-eared = 25%
Slide33Self-Check #1
A rabbit breeder crossed a lop eared rabbit (
Ll
) with another lop eared rabbit (
Ll
). What ratio of offspring have straight ears?
Go back, read your question, and answer any specific questions
1:3
Slide34Self-Check #2
A herpetologist crossed a homozygous fat tailed gecko with a recessive slender tailed gecko. What percent of offspring will have slender tails?
Assign a key (what letters you will use).
F = Fat tailed (dominant)
f = Slender tailed (recessive)
Slide35Self-Check #2
A herpetologist crossed a homozygous fat tailed gecko with a recessive slender tailed gecko. What percent of offspring will have slender tails?
Set up the cross.
FF X
ff
Slide36Self-Check #2
A herpetologist crossed a homozygous fat tailed gecko with a recessive slender tailed gecko. What percent of offspring will have slender tails?
3. Separate Alleles (set up the Punnett square).
f
F
F
f
Slide37Self-Check #2
A herpetologist crossed a homozygous fat tailed gecko with a recessive slender tailed gecko. What percent of offspring will have slender tails?
Fill in the Punnett square
f
F
F
f
Ff
Ff
Ff
Ff
Slide38Self-Check #2
A herpetologist crossed a homozygous fat tailed gecko with a recessive slender tailed gecko. What percent of offspring will have slender tails?
List all the genotypes possible (letter combinations in the square)
Ff
(100%)
Slide39Self-Check #2
A herpetologist crossed a homozygous fat tailed gecko with a recessive slender tailed gecko. What percent of offspring will have slender tails?
List all the phenotypes possible (put the genotypes into word description)
Ff
= Fat tailed
Slide40Self-Check #2
A herpetologist crossed a homozygous fat tailed gecko with a recessive slender tailed gecko. What percent of offspring will have slender tails?
Give ratio or percent or fraction for each
Ff
= Fat tailed (100%)
Slide41Self-Check #2
A herpetologist crossed a homozygous fat tailed gecko with a recessive slender tailed gecko. What percent of offspring will have slender tails?
Go back, read your question, and answer any specific questions
0%
Slide42