WorksheetsChap. 11 Mendal
Total questions: 20
Worksheet time: 10mins
If purple flower color is dominant in pea plants, a cross between P generation purple and white plants will result in
all purple flowers in the F1 generation.
all white flowers in the F1 generation.
all purple flowers in the F1 generation but a lighter purple than in the parents.
mostly purple flowers in the P1 generation, with an occasional white flower.
half of the plants having purple flowers, the other half having white flowers.
If the probability of X occurring is 1 in 4, and the probability of Y occurring is 1 in 5, the probability of both occurring is
(1/4)^2 + (1/5)^2 = (1/16) + (1/25) = (25/400) + (16/400) = 41/400.
(1/4) + (1/5) = (5/20) + (4/20) = 9/20.
(1/4)^2(1/5)^2 = (1/16)(1/25) = 1/400.
(1/4)(1/5) = 1/20.
(1/4 + 1/5^)2 = (5/20 + 4/20)^2 = (9/20)^2 = 81/400.
A testcross is used to
determine if a parent with a dominant trait is heterozygous or homozygous
determine which allele is dominant
determine if the progeny of an experimental cross will get a random assortment of alleles
prove that an organism is true-breeding
cross an individual with a dominant phenotype with a homozygous dominant individual to prove the alleles are indeed dominant
A parent has a genotype of RrYy. What is the probability of having a gamete with the RY genotype?
1/2
1/4
3/4
1/8
0
Your father is heterozygous for a recessive disorder. You know your mom has two "good" alleles. What is the probability that you will have the disorder?
0%
25%
50%
75%
100%
Your father is heterozygous for the recessive disorder phenylketonuria (PKU). You know your mom has two "good" alleles. What is the probability that you will have the disorder?
0% but you will have a 50% chance of passing the "bad" allele on to your children
0% and you don't need to worry about passing the "bad" allele on to your children
25% for you and 25% for your children
50% for you and 50% for your children
50% for you and 25% that you'll pass the "bad" allele on to your children
R is the dominant allele for a round pea, r is the recessive allele for a wrinkled pea. If you cross plants having round peas with plants having wrinkled peas,
both pea plants are homozygous
you are conducting a dihybrid cross.
you are crossing two parental pea plants
the progeny plants will all have wrinkled peas
you will be able to determine if the round pea plant is homozygous or heterozygous
If your mother is heterozygous for Huntington disease, which is caused by a dominant allele, the odds of your inheriting the disorder from her are
1/4
1/2
3/4
1
0
If your mother and father both have cystic fibrosis, which is caused by a recessive allele, the odds of your having cystic fibrosis are
1/4
1/2
3/4
1
0
Round is the dominant trait for a pea; the recessive allele produces a wrinkled pea. How can you obtain true-breeding pea plants having round peas with the least amount of work?
Cross plants having round peas with plants having wrinkled peas. Select round pea plants from the progeny because they are now true-breeding.
Cross plants having round peas with other plants having round peas. Do this for multiple generations.
Cross plants having round peas with plants having wrinkled peas. Select round pea plants from the progeny and do a test cross to determine which parental plants were homozygous dominant. Use these homozygous pea plants as your true-breeding plants.
Cross plants having round peas with plants having wrinkled peas. This will tell you which round pea plants are homozygous dominant and are thus true-breeding.
It's not possible. You can only get true-breeding plants that have wrinkled peas
A cross is done between parents with genotypes aaBbCc and aaBbcc. What is the probability that offspring will have the same genotype as the first parent?
1/8
1/4
3/8
3/16
9/16
A couple are both heterozygous for the dominant allele for polydactyly. They want to have three children. What is the probability that all three children will have polydactyly?
3/4
9/64
1/64
27/64
1/2
Your mother has albinism, which is a recessive trait. You learn that your spouse's mother also has albinism. Neither you nor your spouse have albinism. What are the odds that your first child will have albinism?
1/4
1/2
3/4
1
not enough information
The key difference between incomplete dominance and codominance is
with incomplete dominance, the recessive allele cannot be detected; in codominance, the expression of the recessive allele is apparent.with incomplete dominance it is possible to detect the expression of a recessive allele; in codominance, both alleles contribute equally to the phenotype
with incomplete dominance it is possible to detect the expression of a recessive allele; in codominance, both alleles contribute equally to the phenotype.
with codominance it is possible to detect the expression of a recessive allele; in incomplete dominance, both alleles contribute equally to the phenotype
with incomplete dominance, it is possible to detect the expression of the dominant allele; in codominance, both alleles contribute equally to the phenotype.
the two terms mean the same thing
Two snapdragons heterozygous for alleles that encode red and white flower color are crossed. If the red and white alleles show incomplete dominance, what will be the phenotypes and ratios of the F2 generation?
100% pink
100% red
50% white, 50% red
25% red, 50% pink, 25% white
25% pink, 50% white, 25% red
You have type O blood (genotype ii). Who can you donate blood to in an emergency?
type O only
type B only
type A only
type AB only
types A, B, AB, and O
The different alleles in human blood type are a demonstration of
incomplete dominance
codominance.
dominance and incomplete dominance
dominance and codominance.
dominance, codominance, and incomplete dominance.
Mouse pigmentation is subject to epistasis of the B alleles by the d alleles. B (black) is dominant over b (brown). D is dominant over d. Homozygous d is epistatic to the black and brown genes. Given this information, what genotypes give you a white mouse?
BBdd
Bbdd
bbDD
bbDd
BBdd and Bbdd
We now know that some of the 7 alleles Mendel studied are on the same chromosome in pea plants. Despite this, the law of independent assortment still applies. How can you explain this?
There is recombination via the synaptonemal complex during mitosis.
The law of independent assortment applies to all alleles regardless of their arrangement on chromosomes
There is recombination via the synaptonemal complex during meiosis.
Mendel was a good enough mathematician to design experiments that would result in the predicted ratios.
Mendel was incredibly lucky
A test cross always uses a homozygous recessive organism as one parent.
true
false
