Ask Biology Expert

1. You're working on golden rice, a plant that promises to alleviate nutritional deficiencies in some developing countries. You cross two true breeding plants. One parent is has fat grains, wavy leaves, red flowers and is short in stature, while the other parent expresses the contrasting phenotypes of thin grains, straight leaves, white flowers and is tall in stature. The four pairs of contrasting traits are controlled by four genes, each located on a separate chromosome. In the F1, only fat grains, straight leaves, red flowers, and tall stature were expressed. In the F2, all possible combinations of these traits were expressed in ratios consistent with Mendelian inheritance.
(a) What conclusions can you draw about dominance relationships from the F1 results?
(b) In the F2 results, which phenotype appeared most frequently? find out the probability of this phenotype occurring.
(c) Which F2 phenotype is expected to occur least frequently? find out the probability of this phenotype occurring.
(d) In the F2 generation, what is the probability of getting one or the other parental phenotypes?
(e) If the F1 plants were test crossed, how many different phenotypes would be produced? How does this number compare with the number of different phenotypes in the F2 generation discussed in parts a-d?

2. Red-green color blindness is X-linked recessive. A woman with normal color vision has a father who is red-green color-blind. The woman has four sons, none of whom are color-blind. Assume everyone in the family has a normal complement of chromosomes. Each of the next three statements has an explanation for why none of the sons are color-blind. For each, state if it is possible or not possible, then give the reason for your choice.

i) None of the sons are color-blind because the mother does not carry the color-blindness allele.

ii) None of the sons are color-blind because none of them inherited the color-blindness allele from the mother.

iii) None of the sons are color-blind because the mother inactivated the X chromosome with the recessive color-blindness allele, and that is the one each son inherited.

3. You have discovered a new orange body color gene on the X chromosome of Drosophila similar to the gene that confers orange coat color in cats. You know that X chromosome inactivation in female cats heterozygous for the coat color gene can result in tortoiseshell colored coats. Do you expect to see similar tortoiseshell body color in Drosophila? describe your answer?

4. You are studying the genetics of hair characteristics in mice. You find two new interesting mutants one with abnormally thick hair and one with abnormally curly hair. You describe these new mutants to three of your colleagues. The first colleague says that she has seen the mutants before and that they can be describeed by two codominant alleles of the same gene. The second colleague says he too has seen mutants like these before but tells you that they are due to two incompletely dominant alleles. The third colleague thinks the two mutants can be describeed by two alleles of the same gene and that thick hair is dominant to curly hair. Assume you have a true breeding strain of each mutant. Could you determine which of your colleagues is right by looking at F1 progeny from crossing the two strains or would you have to look at F2 progeny? What would the F1 progeny look like if the mutants were allelic and were i)codominant ii) incompletely dominant or iii) completely dominant?

Biology, Academics

  • Category:- Biology
  • Reference No.:- M927791

Have any Question?


Related Questions in Biology

Case study question -case study - mary 21 years old

Case Study Question - Case Study - Mary, 21 years old, presented to the hospital emergency department with an infected laceration on her left foot. Mary was at a beach resort four days ago, when she trod on a broken glas ...

Assignment -the upper-case blue letters are the 14th exon

Assignment - The upper-case, blue letters are the 14th exon (of 20) in the Hephl1 gene in mice. The lower-case (black) letters are from the flanking introns.  The highlighted bases indicate primers that may be used to ge ...

Question - a pure strain of mendels peas dominant for all

Question - A pure strain of mendel's peas, dominant for all seven of his independently assorting genes, was testcrossed. How many different kinds of gametes could the F1 PRODUCE?

Igfbp2 rbp4 and factor d post bariatric surgeryigfbp2 what

IGFBP2/ RBP4 and Factor D Post Bariatric Surgery IGFBP2 ( what the normal physiological action in the body? And how it affectedby obesity? andpost bariatric surgery?) RBP4 (what the normal physiological action in the bod ...

Assignment on nutrition - q1 task you need to select 2

Assignment on Nutrition - Q1. Task: You need to select 2 different age groups of your choice. You will need to plan balanced meals with snacks for a day. Once you have laid out the meal plan you need to: Explain why the ...

Question - gene cloning a please write the steps to clone

Question - Gene Cloning a) Please write the steps to clone the protease gene from Bacillus strain whose genome sequence is not known. b) Express the protease gene to obtain the enzyme in high yield, please plan your prot ...

Instructions address each question below as it relates to

Instructions: Address each question below as it relates to the caw study given. A patient was brought to the Emergency Department by ambulance with two arrow wounds. One arrow is still in the patient on the left side; en ...

Use of molecular tools and bioinforrnatics in the diagnosis

Use of Molecular Tools and Bioinforrnatics in the Diagnosis Characterization of Enteric Pathogens from a Case Study Purpose: The purpose of this project is to familiarize the student with modern molecular tools and bioin ...

Experiment 1 staining video1 open the media player by

Experiment 1: Staining Video 1. Open the Media Player by clicking on the film-strip button in the lower left of the lab's window frame, as shown below. The Media Player is a repository of images, videos, saved snapshots, ...

Chosen dr jan nolta- stem cell researcher head of uc davis

Chosen Dr. Jan Nolta- Stem Cell Researcher Head of UC Davis Stem Cell Program Director Topic Background: early Stem cells have the ability to develop into many different types of cells. Stem Cell Research is not without ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Why might a bank avoid the use of interest rate swaps even

Why might a bank avoid the use of interest rate swaps, even when the institution is exposed to significant interest rate

Describe the difference between zero coupon bonds and

Describe the difference between zero coupon bonds and coupon bonds. Under what conditions will a coupon bond sell at a p

Compute the present value of an annuity of 880 per year

Compute the present value of an annuity of $ 880 per year for 16 years, given a discount rate of 6 percent per annum. As

Compute the present value of an 1150 payment made in ten

Compute the present value of an $1,150 payment made in ten years when the discount rate is 12 percent. (Do not round int

Compute the present value of an annuity of 699 per year

Compute the present value of an annuity of $ 699 per year for 19 years, given a discount rate of 6 percent per annum. As