Eye colour in humans is controlled by genes: The dominant allele of the gene (B) produces brown eyes. The recessive allele (b) produces blue eyes: homozygous blue-eyed woman married a homozygous brown-eyed man, and they had three children all with brown eyes Copy the following genetic diagram into your answer book, and Show the genotypes of the parents; Complete the following grid using the letters B and b. Woman Man Explain why all of the children had brown eyes One of the couple's brown-eyed sons married a brown-eyed woman and they had five children. Two of the children had blue eyes and three of the children had brown eyes: Use a genetic diagram to explain how two of their children came to have blue eyes.
Added by James B.
Step 1
The man is homozygous for brown eyes, meaning he has two copies of the dominant allele (BB). The genetic diagram would look like this: Woman (bb) x Man (BB) Their possible offspring (using a Punnett square) would be: Bb, Bb, Bb, Bb This means all of their Show more…
Show all steps
Your feedback will help us improve your experience
Anand Jangid and 85 other Biology educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
In eye color, the brown-eyed gene has two alleles where brown (B) is dominant to blue (b). Additionally, the brown-eyed gene is dominant epistatically to the green-eyed gene. This gene also has two alleles where green (G) is dominant to blue (g). What are the phenotypes for the following genotypes? A) BBgg B) BBGG C) bbGg D) BbGg A woman with brown eyes has a mother with blue eyes and a father with brown eyes. She has two sisters, one who has blue eyes and one who has green eyes. What are the genotypes of this woman's parents? Mom: Dad: If the parents from the previous question have another child, what is the probability they have a green-eyed child? A) 25% B) 75% C) 100% D) 50%
Kerissa B.
Genetics: Eye Color Each of two parents has the genotype brown/blue, which consists of the pair of alleles that determine eye color, and each parent contributes one of those alleles to a child. Assume that if the child has at least one brown allele, that color will dominate and the eyes will be brown. (The actual determination of eye color is somewhat more complicated.) a. List the different possible outcomes. Assume that these outcomes are equally likely. b. What is the probability that a child of these parents will have the blue/blue genotype? c. What is the probability that the child will have brown eyes?
David N.
In Drosophila, the autosomal recessive bw causes a dark brown eye, and the unlinked autosomal recessive $s t$ causes a bright scarlet eye. A homozygote for both genes has a white eye. Thus, we have the following correspondences between genotypes and phenotypes: $\begin{aligned} s t^{+} / s t^{+} ; b w^{+} / b w^{+} &=\text {red eye (wild type) } \\ s t^{+} / s t^{+} ; b w / b w &=\text { brown eye } \\ s t / s t ; b w^{+} / b w^{+} &=\text {scarlet eye } \\ s t / s t ; b w / b w &=\text { white eye } \end{aligned}$ Construct a hypothetical biosynthetic pathway showing how the gene products interact and why the different mutant combinations have different phenotypes.
Recommended Textbooks
Biology for AP Courses
Objective Biology for NEET
Introduction to General, Organic and Biochemistry
Transcript
Watch the video solution with this free unlock.
EMAIL
PASSWORD