Quizzes Flashcards
Following diagrams show two different stages of cell division in a mammalian cell where 2n=6. State the type of cell division (meiosis/mitosis) and which stage of cell division is seen in each pictured cell?
6 chromosomes lined up in the middle of the cell
Metaphase in mitosis
Following diagrams show two different stages of cell division in a mammalian cell where 2n=6. State the type of cell division (meiosis/mitosis) and which stage of cell division is seen in each pictured cell?
3 homologous pairs of chromosomes being pulled to each pole of the cell by the mitotic spindle
Anaphase I in meiosis
The following cell is at meiosis anaphase II. What is the diploid chromosome number of this cell?
4 chromatids are being pulled at each pole of the cell by the mitotic spindle
n=4
2n=8 (diploid)
Polydactylism is a genetic, autosomal dominant trait where the individual has extra digits on their hands or toes. Mary has the polydactyl trait (she has six toes on her right foot) but her mother was normal. Mary and her partner Ben (normal) are thinking about having children together. Answer the following questions. Show your work and the formula used for calculations.
What are Mary and Ben’s genotypes?
Mary: Aa
Ben: aa
Polydactylism is a genetic, autosomal dominant trait where the individual has extra digits on their hands or toes. Mary has the polydactyl trait (she has six toes on her right foot) but her mother was normal. Mary and her partner Ben (normal) are thinking about having children together. Answer the following questions. Show your work and the formula used for calculations.
What are the chances that Mary and Ben’s first child will be polydactyl?
50% chance first child will be polydactyl
Polydactylism is a genetic, autosomal dominant trait where the individual has extra digits on their hands or toes. Mary has the polydactyl trait (she has six toes on her right foot) but her mother was normal. Mary and her partner Ben (normal) are thinking about having children together. Answer the following questions. Show your work and the formula used for calculations.
Mary and Ben decide to have 4 children. What is the probability that their first child and the last child will not have the disease?
1/4 chance that first and last child are normal
Polydactylism is a genetic, autosomal dominant trait where the individual has extra digits on their hands or toes. Mary has the polydactyl trait (she has six toes on her right foot) but her mother was normal. Mary and her partner Ben (normal) are thinking about having children together. Answer the following questions. Show your work and the formula used for calculations.
If Mary and Ben have 4 children what is the probability that at least 3 of their children will have the disorder?
5/16 chance that at least 3 of their children will have the disorder
In morning glory purple flower colour (P) is dominant to white (p), and large leaves (L) is dominant to small leaves (l). A test cross of a double heterozygotic plant produced the following progeny in the following numbers. 82 purple flowers, large leaves 72 purple flowers, small leaves 90 white flowers, large leaves 68 white flowers, small leaves
Give the genotypes of the two plants that were crossed and the expected progeny in this cross. What is the expected phenotypic ratio among the progeny?
1 purple flowers, large leaves : 1 purple flowers, small leaves : 1 white flowers, large leaves : 1 white flowers, small leaves
In morning glory purple flower colour (P) is dominant to white (p), and large leaves (L) is dominant to small leaves (l). A test cross of a double heterozygotic plant produced the following progeny in the following numbers. 82 purple flowers, large leaves 72 purple flowers, small leaves 90 white flowers, large leaves 68 white flowers, small leaves
Using a chi-squared test determine whether the data fits the expected model. (Set the critical value at alpha=0.05 and use the Chi squared table). Clearly state your hypothesis and conclusion.
Ho: Without significant difference between the observed and expected, the ratio should be 1:1:1:1 as long as P>0.05 (critical value).
0.20 < P < 0.30
Since P > 0.05 (critical value), we fail to reject Ho since it fits the 1:1:1:1 model.
If a female produces 1 in 5000 eggs with an extra X chromosome due to nondisjunction, what is the expected frequency of XXX females (triple X syndrome) arising from any number of fertilized eggs? (Assume meiosis in males is always normal).
1/10,000
Could a man with type B blood and a woman with type AB produce a child with type O blood? Explain your answer using a Punnett square.
No, they could NOT produce a child with type O blood, because the mother does not have the recessive “i.” The father could either be I^B I^B or I^B i
If Duchenne muscular dystrophy (DMD), an X-linked recessive condition in humans has a frequency of 1/10000 females in a hypothetical population.
What is the frequency of males with DMD in this population?
0.01 or 1/100 males
If Duchenne muscular dystrophy (DMD), an X-linked recessive condition in humans has a frequency of 1/10000 females in a hypothetical population.
Assuming that the population is in Hardy-Weinberg equilibrium, what percentage of the females in the population are carriers/heterozygotes?
1.98%
A randomly mating population has the following genotypic frequencies.
Genotype BB Bb bb
Frequency 0.3 0.25 0.45
Is this population in HW equilibrium?
No this population is NOT in H-W equilibrium because the frequencies are not the same.
A primrose plant is heterozygous for the following autosomal chromosome. If “.” Represents the centromere.
AB.CDEF
ab.edcf
State the mutation that occurred in the chromosome?
Paracentric inversion
