Log in
Biology
3
answers
0
watching
27
views

The maize genes S (s+ , s alleles) and B ( b+ , b alleles) are linked, 40 map units apart. If a doubly heterozygous plant with genotype s+ b / s b+ is self fertilized, what proportion of the progeny will be homozygous s b / s b ?

a. 0.40 b. 0.20 c. 0.50 d. 0.10 e. 0.04

Watch
3
answers
0
watching
27
views

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

Unlock all answers

Get 1 free homework help answer.
Get unlimited access
Already have an account? Log in
Share
Get unlimited access
Already have an account? Log in
Share
Get unlimited access
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
Biology
2nd Edition, 2013
Openstax
ISBN: 9781947172517
Concepts of Biology
OER Edition,
Openstax
ISBN: 9781938168116
Essentials of Biology
5 Edition,
Mader
ISBN: 9781259660269

Related questions

In maize (corn), assume that the genes A and B are linked and 30 map units apart. If a plant of Ab/aB is selfed, what proportion of the progeny would be expected to be of ab/ab genotype? A)2.25% B)15% C)9% D)30% E)4.5%

Can you explain it so i know how to do it in the future instead of just giving me the answer please.

ANSWER ALL the PARTS you can

PART1 Alleles are considered linked if recombination is less than 50% in:

a) a Px P Fl cross

b) an F1 x F1F2 cross

c) an F2 x F2F3 cross

d) an Fl x homozygous recessive cross

e) any F2 progeny x homozygous recessive cross 1.

PART2 If two loci A/a B/b are 9 map units apart, and an Ab/aB individual is testcrossed,

a) There will be 9% AB individuals

b)There will be 91% Ab individuals

c) There will be 4.5% ab individuals

d) There will be 91% recombination individuals

If two genes a and b show 50% recombination genes a and c show 35% recombination, and genes b and show 32% recombination, then

a) Genes a and b are on the same chromosome, and 50 m.u. apart

b) Genes a and b are on different chromosomes

c)Genes a and b are on the same chromosome, and 67 map units apart

d) One cannot tell if genes a and b are on the same or different chromosomes from given data.

PART4 If two genes a and b are 8.3 m.u. a part, one expects to find

a) 8.3% recombinant gametes from a double heterozygous parent

b) 91.7% recombinant gametes from a double heterozygous parent

c) A chiasma between the a and b loci in 8.3% of the meiosis

d) A chiasma between the a and b loci in 91.7% of the meiosis.

PART5 Map distances are most accurate when genes are closely linked because as genes become further apart,

a) They always show independent assortment

b)The chance of multiple crossovers increases

c) They no longer recombine

d) There is chiasma interference

PART6 In a three-point testcross, the most frequent classes of progeny were ABc and abC. The less frequent classes of progeny were AbC and aBc. Which gene is in the middle?

a) Aa

b) B/b

c)C/c

d) It is not possible to tell from just these data

PART7 In a three-point testcross with 100 progeny, there were 16 single crossovers between genes A and B, 29 single crossovers between genes B and C, and 4 double crossovers. The correct gene order was determined to be A-B-C. What is the map distance between A and B?

a) 20%

b) 0.2 m.u

c) 20 m.u.

d) 16 m.u.

e) 29 m.u.

f) 16%

1. A purple flowering, smooth seed dihybrid plant (genotype PpSs) is test crossed with a white flowering, wrinkled seed plant (genotype ppss). These produce progeny in the following numbers of four phenotypes: 14:86:84:16 (purple flower + smooth seed coat: purple flower + wrinkled seed coat: white flower + smooth seed coat: white flower + wrinkled seed coat).

a) What is the expected ratio of progeny phenotypes assuming independent assortment of alleles?

b) Explain how the actual ratio of progeny (above) shows that the two genes are linked.

c)How many map units separate the colour and seed coat genes? Show your calculations.

Weekly leaderboard

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