Log in
Biology
5
answers
0
watching
504
views

Flower diameter in sunflowers is a quantitative trait. A plant with 6-cm flowers, from a highly inbred strain, is crossed to a plant with 30-cm flowers, also from a highly inbred strain. The F1 have 18-cm flowers. F1 × F1 crosses yield F2 plants with flowers ranging from 6 to 30 cm in diameter, in approximately 4-cm intervals (6, 10, 14, 18, 22, 26, 30). An 18-cm F1 plant is crossed to a 6-cm plant. What is the probability of an offspring with one additive allele, if all genes that influence this trait are unlinked?

1/3

1/4

1/6

3/8

1/16

Watch
5
answers
0
watching
504
views

For unlimited access to Homework Help, a Homework+ subscription is required.

Unlock all answers

Get 1 free homework help answer.
Already have an account? Log in
Share
Already have an account? Log in
Share
Already have an account? Log in
Share
Already have an account? Log in
Share
Bunny Greenfelder
Bunny GreenfelderLv2
28 Sep 2019
Already have an account? Log in
Share

Related textbook solutions

Molecular Cell Biology
8 Edition,
Lodish
ISBN: 9781464183393
Biology: Science for Life with Physiology
6 Edition,
Belk
ISBN: 9780134555430
Concepts of Biology
OER Edition,
Openstax
ISBN: 9781938168116
Biology
2nd Edition, 2013
Openstax
ISBN: 9781947172517
Essentials of Biology
5 Edition,
Mader
ISBN: 9781259660269

Related questions

A homozygous plant with 20 cm diameter flowers is crossed with a homozygous plant of the same species with 40 cm diameter flowers. The F1 plants all have 30 cm diameter flowers. In the F2 generation (N=512 plants), 2 plants have 20 cm diameter flowers and 2 plants have 40 cm diameter flowers. The rest of the plants have flowers ranging in sizes in between 20-40 cm in diameter.

(a) What frequency distribution of flower diameter do you expect to see in the F2 generation?

(b) What frequency distribution of flower diameter do you expect to see in the progeny of backcross between an F1 plant and the 40 cm diameter flowered parent?


explain the answers please. thank you

1. A true breeding tall pea line is crossed with atrue breeding short line. The F1 plants are all short. The F1 arecrossed with themselves to produce an F2. If the difference (tallvs. short) is due to a single locus, what proportion of the F2individuals do you expect to be tall?

2. Imagine that a researcher crossed the peas in theexample above, and counted 100 F2. 86 were short. 14 were tall. Doa chisquare test to see whether the results conform to a singlelocus cross with the allele coding for short plants dominant to theallele coding for tall plants.

3. A clematis from a true-breeding line with whiteflowers and short corollas (line A) is crossed to a clematis from atrue-breeding line with deep red flowers and long corollas (lineB). The resulting offspring, the F1, are all pink-flowered, withcorollas of medium length. An individual from the F1 iscrossed to an individual from line A. The resulting F2 offspringare as follows: 25% white flowers and short corollas, 25% whiteflowers with medium corollas, 25% pink flowers with short corollas,25% pink flowers with medium corollas.
What is the most likely genetic mechanism determining flower colorand corolla length? If a plant from the F1 listed above were selfed(crossed with itself), what proportion of the F2 offspring wouldyou expect to be white flowered with short corollas?

4. A man and a woman walk into a genetic counselor’soffice. They have just had a child diagnosed with situs inversus, acomplete transposition of the internal organs from left to right,and vice versus. This condition usually produces no obvioussymptoms. It is caused by an autosomal recessive allele. What isthe chance that their next child will have the same condition? Whatmight this suggest about the parents?
Another man and woman walk into the same office. The father is anachondroplasic dwarf. The mother is of normal stature. (Look upachondroplasia, it is a lethal dominant). What is the chance thattheir first child will be a dwarf?

Please show work! (:

11. You suspect that two genes interact with one another to determine the product of a pathway you are studying. You cross two pure breeding plants—one with white flowers and one with pink—to make F1 individuals that have blue flowers. You cross the F1 generation and observe the following numbers of individuals with different phenotypes: Number of individuals Phenotype 91 Blue 30 Pink 39 White Which pathway best explains these results? (Note that arrows indicate enzymatic reactions carried out by products of genes 1 and 2. Assume that buildup of metabolites will determine flower color.)

Question 12 and 13: Consider the biochemical pathway presented below. This pathway determines pigment production in pea flowers. (Note: gene products are required for each reaction to proceed.)

12. Do you expect that genes A and B will interact with one another?

A. Yes B. No C. Insufficient information to determine

13. What phenotype ratio would you expect in offspring produced by crossing AaBb parents?

A. 9:3:3:1 (blue : green : yellow : white) B. 9:3:4 (blue : green : white) C. 9:7 (blue : white) D. 15:1 (blue : white)

14. How can haplosufficiency explain dominance of an allele that codes for a functional protein over a null (loss of function) allele?

A) a single functional copy of the gene produces sufficient gene product for normal biological function B) a single functional copy of the gene produces insufficient gene product for normal biological function C) the null allele produces a product that interferes with proper function of the normal allele D) the null allele produces a product that does not interfere with proper function of the normal allele E) the null allele rapidly mutates to reacquire normal functionality

15. In a plant species with genes A and B, you have isolated recessive mutant alleles at each locus, which you call a and b. You would like to know whether these two genes are linked. To test this hypothesis, you obtain an individual that is heterozygous at both genes (AB/ab) and perform a test cross. Which results would be most consistent with these loci being tightly linked? (Results are counts of the numbers of offspring from the testcross.)

A. Ab/ab 390 aB/ab 410 AB/ab 350 ab/ab 420

B. Ab/ab 80 aB/ab 73 AB/ab 760 ab/ab 754

C. Ab/ab 700 aB/ab 695 AB/ab 56 ab/ab 59

D. Ab/ab 400 aB/ab 65 AB/ab 50 ab/ab 659

Weekly leaderboard

Home
Homework Help 3,900,000
Biology 460,000
Start filling in the gaps now
Log in