BSC 1010 Lecture Notes - Lecture 12: Dihybrid Cross, Pleiotropy, Zygosity

44 views2 pages

olivecattle778

15 May 2017

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

A cross used to determine the genotype with an individual with dominant phenotype. In a typical monohybrid cross, all of the offspring in which generation will exhibit a single trait without blending? autosomal dominant, autosomal recessive, and x-linked recessive. Pleiotropy an allele which has more than one effect on the phenotype. In humans, brown eyes are dominant over blue eyes. A brown-eyed woman who has a blue- eyed child has the genotype heterozygous. If an albino woman is married to a man with normal coloring and they have an albino child, what is the genotype of the man? both heterozygous. If 25% of the offspring of one set of parents show the recessive phenotype, the parents were probably. Amniocentesis reveals that an embryo has tay-sachs disease. What are the genotypes of the parents if they appear normal (t = tay-sachs; tay-sachs is a recessive disease)? multiple alleles. The inheritance of blood types in humans can be explained by.

Related Questions

1. In humans, right-handedness (R) is dominant to left-handedness (r), and brown eyes (B) are usually dominant to blues eyes (b).

a) What are the genotypes of gametes produced by a person heterozygous for both traits?

b) What are the genotypes of gametes for a person heterozygous for brown eyes, but homozygous recessive for left-handedness?

c) Set up a Punnett square for a couple that is heterozygous for both traits. What is the probability that if their first child is brown-eyed and left-handed that the second child is blue-eyed and left-handed?

d) A right-handed, blue-eyed woman marries a right-handed, brown-eyed man. They have two children, one left-handed and brown-eyed and the other right-handed and blue-eyed. By a later marriage with another man, who is also right-handed and brown-eyed, she has seven more children, all of whom are right-handed and brown-eyed. What are the genotypes of the woman and her two husbands?

1. A person is described as a carrier for a particular genetic disease. What does this tell you about their genotype?

2. For any given gene, the principle of independent segregation predicts that each gamete produced as a result of meiosis will contain ____________________

3. A pair of alleles is said to be heterozygous when:

4. In a diploid species, cells can have up to ___ alleles of a particular gene.

5. In a cross between a homozygous dominant parent and a homozygous recessive parent, the number of phenotypic classes observed in the offspring is ______

6. For a person of genotype Xx, the genotype of their gametes may be ______________

7. In a "test cross", an individual of unknown genotype is crossed with a ___ individual to determine the unknown genotype.

8. An albino woman has a child with a phenotypically normal man with no family history of albinism (which is a rare recessive disorder). What percentage of their children are likely to be albino?

9. An individual with the dominant phenotype, but an unknown genotype, is test-crossed, and all of the offspring exhibit the dominant phenotype. The genotype of the unknown individual is ______________

10. If two heterozygous individuals for a recessive disease (carriers) have a child, what is the chance that their child will develop the disease?

11. In a monohybrid cross between two true-breeding parents that both exhibit the dominant phenotype, ___ percent of the offspring will exhibit the recessive phenotype.

12. In a particular type of tomato plant, red fruit is dominant over yellow fruit, and dwarf height is a recessive trait. If two heterozygous plants were crossed, what proportion of the offspring would show the dominant phenotype?

13. In a cross between a BbRr individual and a BBRR one, what do the following represent: BR, Br, bR, br?

14. In humans, the gene that determines whether an embryo develops as a male or a female is carried on _____________

amaranthhare726

Sample questions from a past test on Mendelian Genetics

1)A woman and her spouse both show the normal phenotype for pigmentation, but both had one parent who was an albino. Albinism is an autosomal recessive trait.
What is the probability that their fourth child will have a homozygous genotype?
a. 0 b. 1?4 c. 1?2 d. 3?4. e. 1

2)Black fur in mice (B) is dominant to brown fur (b). Short tails (T) is dominant to long tails (t). What fraction of the progeny (offspring) of the cross BbTt X BBtt will have black fur and long tails?
a. 1/16 b. 3/16 c. 3/8 d. 1?2 e. 9/16

BSC 1010 Lecture Notes - Lecture 12: Dihybrid Cross, Pleiotropy, Zygosity

Document Summary

Get access

Related Documents

BSC 1010 Chapter Notes - Chapter 20: Allele Frequency, Assortative Mating, Genotype Frequency

BSC 1010 Chapter Notes - Chapter 12: Egg Cell, Phenotype, Pangenesis

BIO 101 Lecture Notes - Lecture 17: Punnett Square, Blue Hair, Human Hair Color

Related Questions