Define Genetics with punnet square7 questions , question and answer.
Sometimes, we only know about the offspring and we want to learn about the parents. See is you can figure out what the parents genotypes are based on the following information: In pea plants, yellow seeds (Y) are dominant and green seeds (y) are recessive. A pea plant with yellow seeds is crossed with a pea plant with green seeds. The resulting offspring have about equal numbers of yellow and green seeded plants.
What are the genotypes of the parents? Explain your answer.
Sometimes, you can have two genes that have equal dominance, such as cases like incomplete dominance and codominance.
In humans, straight hair (SS) and curly hair (CC) are equally dominant. When you inherit one of each allele, the result is wavy hair (SC).
What type of dominance is being illustrated – codominance or incomplete dominance? Explain your answer.
Using the information above, create a Punnett square to illustrate the offspring of a curly haired female with a wavy haired male.
What are the chances of the having a curly haired child? Show your work.
Parent Genotypes: X
In cows, red(RR) and white (WW) are equally dominant. When you inherit one of each allele, the result would be roan (spotted with both red and white patches)(RW).
What type of dominance is being illustrated – codominance or incomplete dominance? Explain your answer.
Using the information above, create a Punnett square to illustrate the offspring of a roan cow with a red cow.
What are the chances of the having a roan offspring? Show your work.
Parent Genotypes: X
Some genes are inherited on the sex chromosomes, X and Y. These are known as sex-linked genes.
Most of these sex-linked traits are recessive and are carried on the X chromosomes. Recall that females have the sex chromosomes XX, and males have the sex chromosomes XY. Based on this information, who do you think is more likely to inherit a sex-linked trait? Explain your answer.
Hemophilia is a sex-linked trait. A person with hemophilia is lacking certain proteins that are necessary for normal blood clotting. Hemophilia is caused by a recessive allele on the X- chromosome (that means you will use a lower case h attached to the X chromosome if the individual has the gene for hemophilia). Recall that a women will have two allele (XHXH, XHXh, or XhXh) but a man will only have one allele (XH or Xh)
Would a woman with the genotype XHXH phenotypically have hemophilia? Explain your answer:
Create a cross between a woman is heterozygous (a carrier) for hemophilia and a normal man. What percentage of their offspring would have hemophilia? Show your work.
Parent Genotypes: X
A dihybrid cross can be used when looking at two different traits. Use the following information to determine the phenotypes of the below individuals given their genotypes:
P= Purple flowers p= White flowers T= Tall t= Short
PpTT:
pptt:
ppTt:
